oracle数据类型

Oracle/PLSQL: Data Types

The following is a list of datatypes available in Oracle.

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Character Datatypes

Data Type Syntax	Oracle 9i	Oracle 10g	Oracle 11g	Explanation (if applicable)
char(size)	Maximum size of 2000 bytes.	Maximum size of 2000 bytes.	Maximum size of 2000 bytes.	Where size is the number of characters to store. Fixed-length strings. Space padded.
nchar(size)	Maximum size of 2000 bytes.	Maximum size of 2000 bytes.	Maximum size of 2000 bytes.	Where size is the number of characters to store. Fixed-length NLS string Space padded.
nvarchar2(size)	Maximum size of 4000 bytes.	Maximum size of 4000 bytes.	Maximum size of 4000 bytes.	Where size is the number of characters to store. Variable-length NLS string.
varchar2(size)	Maximum size of 4000 bytes.	Maximum size of 4000 bytes.	Maximum size of 4000 bytes.	Where size is the number of characters to store. Variable-length string.
long	Maximum size of 2GB.	Maximum size of 2GB.	Maximum size of 2GB.	Variable-length strings. (backward compatible)
raw	Maximum size of 2000 bytes.	Maximum size of 2000 bytes.	Maximum size of 2000 bytes.	Variable-length binary strings
long raw	Maximum size of 2GB.	Maximum size of 2GB.	Maximum size of 2GB.	Variable-length binary strings. (backward compatible)

Numeric Datatypes

Data Type Syntax	Oracle 9i	Oracle 10g	Oracle 11g	Explanation (if applicable)
number(p,s)	Precision can range from 1 to 38. Scale can range from -84 to 127.	Precision can range from 1 to 38. Scale can range from -84 to 127.	Precision can range from 1 to 38. Scale can range from -84 to 127.	Where p is the precision and s is the scale. For example, number(7,2) is a number that has 5 digits before the decimal and 2 digits after the decimal.
numeric(p,s)	Precision can range from 1 to 38.	Precision can range from 1 to 38.	Precision can range from 1 to 38.	Where p is the precision and s is the scale. For example, numeric(7,2) is a number that has 5 digits before the decimal and 2 digits after the decimal.
float
dec(p,s)	Precision can range from 1 to 38.	Precision can range from 1 to 38.	Precision can range from 1 to 38.	Where p is the precision and s is the scale. For example, dec(3,1) is a number that has 2 digits before the decimal and 1 digit after the decimal.
decimal(p,s)	Precision can range from 1 to 38.	Precision can range from 1 to 38.	Precision can range from 1 to 38.	Where p is the precision and s is the scale. For example, decimal(3,1) is a number that has 2 digits before the decimal and 1 digit after the decimal.
integer
int
smallint
real
double precision

Date/Time Datatypes

Data Type Syntax	Oracle 9i	Oracle 10g	Oracle 11g	Explanation (if applicable)
date	A date between Jan 1, 4712 BC and Dec 31, 9999 AD.	A date between Jan 1, 4712 BC and Dec 31, 9999 AD.	A date between Jan 1, 4712 BC and Dec 31, 9999 AD.
timestamp (fractional seconds precision)	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	Includes year, month, day, hour, minute, and seconds. For example: timestamp(6)
timestamp (fractional seconds precision) with time zone	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	Includes year, month, day, hour, minute, and seconds; with a time zone displacement value. For example: timestamp(5) with time zone
timestamp (fractional seconds precision) with local time zone	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	fractional seconds precisionmust be a number between 0 and 9. (default is 6)	Includes year, month, day, hour, minute, and seconds; with a time zone expressed as the session time zone. For example: timestamp(4) with local time zone
interval year (year precision) to month	year precision is the number of digits in the year. (default is 2)	year precision is the number of digits in the year. (default is 2)	year precision is the number of digits in the year. (default is 2)	Time period stored in years and months. For example: interval year(4) to month
interval day (day precision) to second (fractional seconds precision)	day precisionmust be a number between 0 and 9. (default is 2) fractional seconds precisionmust be a number between 0 and 9. (default is 6)	day precisionmust be a number between 0 and 9. (default is 2) fractional seconds precisionmust be a number between 0 and 9. (default is 6)	day precisionmust be a number between 0 and 9. (default is 2) fractional seconds precisionmust be a number between 0 and 9. (default is 6)	Time period stored in days, hours, minutes, and seconds. For example: interval day(2) to second(6)

Large Object (LOB) Datatypes

Data Type Syntax	Oracle 9i	Oracle 10g	Oracle 11g	Explanation (if applicable)
bfile	Maximum file size of 4GB.	Maximum file size of 232-1 bytes.	Maximum file size of 264-1 bytes.	File locators that point to a binary file on the server file system (outside the database).
blob	Store up to 4GB of binary data.	Store up to (4 gigabytes -1) * (the value of the CHUNK parameter of LOB storage).	Store up to (4 gigabytes -1) * (the value of the CHUNK parameter of LOB storage).	Stores unstructured binary large objects.
clob	Store up to 4GB of character data.	Store up to (4 gigabytes -1) * (the value of the CHUNK parameter of LOB storage) of character data.	Store up to (4 gigabytes -1) * (the value of the CHUNK parameter of LOB storage) of character data.	Stores single-byte and multi-byte character data.
nclob	Store up to 4GB of character text data.	Store up to (4 gigabytes -1) * (the value of the CHUNK parameter of LOB storage) of character text data.	Store up to (4 gigabytes -1) * (the value of the CHUNK parameter of LOB storage) of character text data.	Stores unicode data.

Rowid Datatypes

Data Type Syntax	Oracle 9i	Oracle 10g	Oracle 11g	Explanation (if applicable)
rowid	The format of the rowid is: BBBBBBB.RRRR.FFFFF Where BBBBBBB is the block in the database file; RRRR is the row in the block; FFFFF is the database file.	The format of the rowid is: BBBBBBB.RRRR.FFFFF Where BBBBBBB is the block in the database file; RRRR is the row in the block; FFFFF is the database file.	The format of the rowid is: BBBBBBB.RRRR.FFFFF Where BBBBBBB is the block in the database file; RRRR is the row in the block; FFFFF is the database file.	Fixed-length binary data. Every record in the database has a physical address orrowid.
urowid(size)				Universal rowid. Where size is optional.

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1 Data Types

A data type defines a set of values. A reference to a data type specifies the set of values that can occur in a given context. A data type is associated with each value retrieved
from a table or computed in an expression and each constant.

TimesTen follows the ODBC standard for type conversion. For more information, refer to ODBC API reference documentation, which is available from Microsoft or a variety of third parties. The following site contains Microsoft's ODBC API reference documentation:

http://msdn.microsoft.com/en-us/library/ms714562(VS.85).aspx

If you are using IMDB Cache, see "Mappings between Oracle and TimesTen data types" in Oracle
In-Memory Database Cache User's Guide. This section compares valid data types for creating cache group columns, as well as type conversions for passthrough queries.

The following subjects describe data types in TimesTen:

Type specifications

ANSI SQL data types

Types supported for backward compatibility in Oracle type mode

TimesTen type mapping

Character data types

Numeric data types

BINARY and VARBINARY data types

Numeric precedence

LOB data types

ROWID data type

Datetime data types

TimesTen intervals

Storage requirements

Data type comparison rules

Data type conversion

Null values

INF and NAN

Overflow and truncation

Underflow

Replication limits

TimesTen type mode (backward compatibility)

Type specifications

TimesTen supports the data types in Table 1-1 in the default Oracle type mode.
Type mode is a data store attribute, where

TypeMode=0

indicates Oracle type mode and

TypeMode=1

indicates TimesTen mode. For more information on data type modes, see "TimesTen
type mode (backward compatibility)" and "TypeMode" inOracle
TimesTen In-Memory Database Reference.

Table 1-1 Data types supported in Oracle type mode

Data type	Description
BINARY ( n )	Fixed-length binary value of n bytes. Legal values for n range from 1 to 8300. BINARY data is padded to the maximum column size with trailing zeroes. Alternatively, specify TT_BINARY ( n ) . For more details, see "BINARY and VARBINARY data types".
BINARY_DOUBLE	A 64-bit floating-point number. BINARY_DOUBLE is a double-precision native floating point number that supports +Inf , -Inf , and NaN values. BINARY_DOUBLE is an approximate numeric value consisting of an exponent and mantissa. You can use exponential or E-notation. BINARY_DOUBLE has binary precision 53. Minimum positive finite value: 2.22507485850720E-308 Maximum positive finite value: 1.79769313486231E+308 For more details, see "BINARY_DOUBLE".
BINARY_FLOAT	A 32-bit floating-point number. BINARY_FLOAT is a single-precision native floating-point type that supports +Inf , -Inf , and NaN values. BINARY_FLOAT is an approximate numeric value consisting of an exponent and mantissa. You can use exponential or E-notation. BINARY_FLOAT has binary precision 24. Minimum positive finite value: 1.17549E-38F Maximum positive finite value: 3.40282E+38F For more details, see "BINARY_FLOAT".
BLOB	A binary large object. Variable-length binary value with a maximum size of 16 MB. For more details, see "BLOB".
CHAR [ACTER][( n [BYTE|CHAR])]	Fixed-length character string of length n bytes or characters. Default is one byte. BYTE indicates that the column has byte-length semantics. Legal values for n range from a minimum of one byte to a maximum of 8300 bytes. CHAR indicates that the column has character-length semantics. The minimum CHAR length is one character. The maximum CHAR length depends on how many characters fit in 8300 bytes. This is determined by the database character set in use. For character set AL32UTF8 , up to four bytes per character may be needed, so the CHAR length limit ranges from 2075 to 8300 depending on the character set. A zero-length string is interpreted as NULL . CHAR data is padded to the maximum column size with trailing blanks. Blank-padded comparison semantics are used. Alternatively, specify ORA_CHAR[( n [BYTE|CHAR])] . For more details, see "CHAR".
CLOB	A character large object containing single-byte or multibyte characters. Variable-length large object with a maximum size of 4 MB. For more details, see "CLOB".
DATE	Stores date and time information: century, year, month, day, hour, minute, and second. Format is: YYYY-MM-DD HHMMSS . Valid date range is from January 1, 4712 BC to December 31, 9999 AD. There are no fractional seconds. Alternatively, specify ORA_ DATE . For more details, see "DATE".
INTERVAL [+/-] IntervalQualifier	TimesTen partially supports interval types, expressed with the type INTERVAL and an IntervalQualifier . An IntervalQualifier can only specify a single field type with no precision. The default leading precision is eight digits for all interval types. The single field type can be: year, month, day, hour, minute, or second. Currently, interval types can be specified only with a constant. Note: You cannot specify a column of an interval type. These are non-persistent types used in SQL expressions at runtime. In addition, for those comparisons where an interval data type is returned, the interval data type cannot be the final result of a complete expression. The EXTRACT function must be used to extract the desired component of this interval result. For more details, see "TimesTen intervals".
NCHAR [( n ) ]	Fixed-length string of n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. NCHAR character limits are half the byte limits so the maximum size is 4150. A zero-length string is interpreted as NULL . NCHAR data is padded to the maximum column size with U+0020 SPACE . Blank-padded comparison semantics are used. Alternatively, specify ORA_NCHAR[( n )] . For more details, see "NCHAR".
NCLOB	A national character large object containing Unicode characters. Variable-length character value with a maximum size of 4 MB. For more details, see "NCLOB".
NUMBER[( p [, s ])]	Number having precision and scale. The precision ranges from 1 to 38 decimal. The scale ranges from -84 to 127. Both precision and scale are optional. If you do not specify a precision or a scale, TimesTen assumes the maximum precision of 38 and flexible scale. NUMBER supports negative scale and scale greater than precision. NUMBER stores zero as well as positive and negative fixed numbers with absolute values from 1.0 x 10-130 to (but not including) 1.0 x 10126. If you specify an arithmetic expression whose value has an absolute value greater than or equal to 1.0 x 10126, then TimesTen returns an error. For more details, see "NUMBER".
NVARCHAR2( n )	Variable-length string of n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. NVARCHAR2 character limits are half the byte limits so the maximum size is 2,097,152 (221). You must specify n . A zero-length string is interpreted as NULL . Nonpadded comparison semantics are used. Alternatively, specify ORA_NVARCHAR2( n ) . For more details, see "NVARCHAR2".
ROWID	An 18-byte character string that represents the address of a table row or materialized view row. Specify a literal ROWID value as a CHAR constant enclosed in single quotes. For more details, see "ROWID data type".
TIME	A time of day between 00:00:00 (midnight) and 23:59:59 (11:59:59 pm), inclusive. The format is: HH:MI:SS . Alternatively, specify TT_TIME . For more details, see "TIME".
TIMESTAMP [( fractional_seconds_precision )]	Stores year, month, and day values of the date plus hour, minute, and second values of the time. The fractional_seconds_precision is the number of digits in the fractional part of the seconds field. Valid date range is from January 1, 4712 BC to December 31, 9999 AD. TT_TIMESTAMP has a smaller storage size than TIMESTAMP . TT_TIMESTAMP is faster than TIMESTAMP because TT_TIMESTAMP is an eight-byte integer containing the number of microseconds since January 1, 1754. Comparisons are very fast. TIMESTAMP has a larger range than TT_TIMESTAMP in that TIMESTAMP can store date and time data as far back as 4712 BC. TIMESTAMP also supports up to nine digits of fractional second precision whereas TT_TIMESTAMP supports six digits of fractional second precision. The fractional seconds precision range is 0 to 9. The default is 6. Format is: YYYY-MM-DD HH:MI:SS [.FFFFFFFFF] Alternatively, specify ORA_TIMESTAMP[( fractional_seconds_precision )] For more details, see "TIMESTAMP".
TT_BIGINT	A signed eight-byte integer in the following range: -9,223,372,036,854,775,808 (-263) to 9,223,372,036,854,775,807 (263-1). Use TT_BIGINT rather than the NUMBER data type. TT_BIGINT is more compact and offers faster performance than the NUMBER type. If you need to store greater than 19-digit integers, use NUMBER ( p ) where p > 19. For more details, see "TT_BIGINT".
TT_DATE	Stores date information: century, year, month, and day. The format is YYYY-MM-DD , where MM is expressed as an integer such as 2006-10-28. Valid dates are between 1753-01-01 (January 1, 1753) and 9999-12-31 (December 31, 9999). For more details, see "TT_DATE".
TT_INTEGER	A signed integer in the range -2,147,483,648 (-231) to 2,147,483,647 (231-1). TT_INTEGER is a native signed integer data type. Use TT_INTEGER rather than INTEGER . INTEGER maps to the NUMBER data type. TT_INTEGER is more compact and offers faster performance than the NUMBER type. If you need to store greater than 19-digit integers, use NUMBER ( p ) where p > 19. For more details, see "TT_INTEGER".
TT_SMALLINT	A native signed 16-bit integer in the range -32,768 (-215) to 32,767 (215-1). Use TT_SMALLINT rather than SMALLINT . SMALLINT maps to the NUMBER data type. TT_SMALLINT is more compact and offers faster performance than the NUMBER type. If you need to store greater than 19-digit integers, use NUMBER ( p ) where p > 19. For more details, see "TT_SMALLINT".
TT_TIMESTAMP	A date and time between 1753-01-01 00:00:00 (midnight on January 1, 1753) and 9999-12-31 23:59:59 pm (11:59:59 pm on December 31, 9999), inclusive. Any values for the fraction not specified in full microseconds result in a " Data Truncated " error. The format is YYYY-MM-DD HH:MI:SS [.FFFFFFFFF] . TT_TIMESTAMP has a smaller storage size than TIMESTAMP and is faster than TIMESTAMP because TT_TIMESTAMP is an eight-byte integer containing the number of microseconds since January 1, 1754. Comparisons are very fast. TIMESTAMP has a larger range than TT_TIMESTAMP in that TIMESTAMP can store date and time data as far back as 4712 BC. TIMESTAMP also supports up to nine digits of fractional second precision whereas TT_TIMESTAMP supports six digits of fractional second precision. You can specify TT_TIMESTAMP(6) . For more details, see "TT_TIMESTAMP".
TT_TINYINT	Unsigned integer ranging from 0 to 255 (28-1). Use TT_TINYINT rather than the NUMBER data type. TT_TINYINT is more compact and offers faster performance than the NUMBER type. If you need to store greater than 19-digit integers, use NUMBER( p ) where p > 19. Since TT_TINYINT is unsigned, the negation of a TT_TINYINT is a TT_SMALLINT . For more details, see "TT_TINYINT".
VARBINARY ( n )	Variable-length binary value having maximum length n bytes. Legal values for n range from 1 to 4194304 (222). Alternatively, specify TT_VARBINARY( n ) . For more details, see "BINARY and VARBINARY data types".
VARCHAR[2]( n [BYTE|CHAR])	Variable-length character string having maximum length n bytes or characters. BYTE indicates that the column has byte-length semantics. Legal values for n range from a minimum of one byte to a maximum 4194304 (222) bytes. You must specify n . CHAR indicates that the column has character-length semantics. A zero-length string is interpreted as NULL . Nonpadded comparison semantics are used. Do not use the VARCHAR type. Although it is currently synonymous with VARCHAR2 , the VARCHAR type is scheduled to be redefined. Alternatively, specify ORA_VARCHAR2( n [BYTE|CHAR]) . For more details, see "VARCHAR2".

ANSI SQL data types

TimesTen supports ANSI SQL data types in Oracle type mode. These data types are converted to TimesTen data types with data stored as TimesTen data types.Table
1-2 shows how the ANSI SQL data types are mapped to TimesTen data types.

Table 1-2
Data type mapping: ANSI SQL to TImesTen

ANSI SQL data type	TimesTen data type
CHARACTER VARYING( n [BYTE|CHAR]) or CHAR VARYING( n [BYTE|CHAR])	VARCHAR2( n [BYTE|CHAR]) Character semantics is supported.
DOUBLE [PRECISION]	NUMBER Floating-point number with a binary precision of 126. Alternatively, specify FLOAT(126) or ORA_FLOAT(126) .
FLOAT[( b )]	NUMBER Floating-point number with binary precision b . Acceptable values for b are between 1 and 126 (binary digits). FLOAT is an exact numeric type. Use FLOAT to define a column with a floated scale and a specified precision. A floated scale is supported with the NUMBER type, but you cannot specify the precision. A lower precision requires less space, so because you can specify a precision with FLOAT , it may be more desirable than NUMBER . If you do not specify b , then the default precision is 126 binary (38 decimal). BINARY_FLOAT and BINARY_DOUBLE are inexact numeric types and are therefore different floating types than FLOAT . In addition, the semantics are different between FLOAT and BINARY_FLOAT / BINARY_DOUBLE because BINARY_FLOAT and BINARY_DOUBLE conform to the IEEE standard. Internally, FLOAT is implemented as type NUMBER . Alternatively, specify ORA_FLOAT . For example: FLOAT(24) = ORA_FLOAT(24) FLOAT(53) = ORA_FLOAT(53 ) FLOAT( n ) = ORA_FLOAT( n )
INT[EGER]	NUMBER (38,0) TT_INTEGER is a native 32-bit integer type. Use TT_INTEGER , as this data type is more compact and offers faster performance than the NUMBER type.
NATIONAL CHARACTER( n ) or NATIONAL CHAR ( n )	NCHAR( n )
NATIONAL CHARACTER VARYING( n ) or NATIONAL CHAR VARYING( n ) or NCHAR VARYING( n )	NVARCHAR2( n )
NUMERIC [( p [, s ])] or DEC[IMAL][( p [, s ])]	NUMBER( p,s ) Specifies a fixed-point number with precision p and scale s. This can only be used for fixed-point numbers. If no scale is specified, s defaults to 0.
REAL	NUMBER Floating-point number with a binary precision of 63. Alternatively, specify ORA_FLOAT(63) or FLOAT(63) .
SMALLINT	NUMBER(38,0) TT_SMALLINT is a native signed integer data type. Using TT_SMALLINT is more compact and offers faster performance than the NUMBER type.

Types supported for backward compatibility in Oracle type mode

TimesTen supports the data types shown in Table 1-3 for backward compatibility in Oracle type mode.

Table
1-3 Data types supported for backward compatibility in Oracle type mode

Data type	Description
TT_CHAR[( n [BYTE|CHAR])]	Fixed-length character string of length n bytes or characters. Default is one byte. BYTE indicates that the column has byte-length semantics. Legal values for n range from a minimum of one byte to a maximum 8300 bytes. CHAR indicates that the column has character-length semantics. The minimum CHAR length is one character. The maximum CHAR length depends on how many characters fit in 8300 bytes. This is determined by the database character set in use. For character set AL32UTF8 , up to four bytes per character may be needed, so the CHAR length limit ranges from 2075 to 8300 depending on the character set. If you insert a zero-length (empty) string into a column, the SQL NULL value is inserted. This is true in Oracle type mode only. TT_CHAR data is padded to the maximum column size with trailing blanks. Blank-padded comparison semantics are used.
TT_DECIMAL[( p [, s ])]	An exact numeric value with a fixed maximum precision (total number of digits) and scale (number of digits to the right of the decimal point). The precision p must be between 1 and 40. The scale s must be between 0 and p . The default precision is 40 and the default scale is 0. Use the NUMBER data type, which offers better performance, rather than TT_DECIMAL .
TT_NCHAR[( n )]	Fixed-length string of n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. NCHAR character limits are half the byte limits so the maximum size is 4150. If you insert a zero-length (empty) string into a column, the SQL NULL value is inserted. This is true in Oracle type mode only. TT_NCHAR data is padded to the maximum column size with U+0020 SPACE . Blank-padded comparison semantics are used.
TT_NVARCHAR( n )	Variable-length string of n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. TT_NVARCHAR character limits are half the byte limits so the maximum size is 2,097,152 (221). You must specify n . If you insert a zero-length (empty) string into a column, the SQL NULL value is inserted. This is true in Oracle type mode only. Blank-padded comparison semantics are used.
TT_VARCHAR( n [BYTE|CHAR])	Variable-length character string having maximum length n bytes or characters. You must specify n . BYTE indicates that the column has byte-length semantics. Legal values for n range from a minimum of 1 byte to a maximum 4194304 (222) bytes. CHAR indicates that the column has character-length semantics. If you insert a zero-length (empty) string into a column, the SQL NULL value is inserted. This is true in Oracle type mode only. Blank-padded comparison semantics are used.

Table 1-4 Data type mapping: TimesTen data type to TimesTen data type in Oracle type mode

TimesTen data type	TimesTen data type in Oracle type mode
BIGINT	TT_BIGINT In Oracle type mode, specify TT_BIGINT . For more information on TT_BIGINT , see "Type specifications".
BINARY( n )	BINARY( n ) In Oracle type mode, the data type has the same name. For more information on BINARY( n ) , see"Type specifications".
CHAR[ACTER][( n )]	TT_CHAR[( n [BYTE|CHAR])] In Oracle type mode, specify TT_CHAR . Character semantics is supported. For more information on type TT_CHAR , see "Types supported for backward compatibility in Oracle type mode".
DATE	TT_DATE In Oracle type mode, specify TT_DATE . For more information on TT_DATE , see "Type specifications".
DEC[IMAL][( p [, s ])] or NUMERIC[( p [, s ])]	TT_DECIMAL[( p [, s ])] In Oracle type mode, specify TT_DECIMAL . For more information on TT_DECIMAL , see "Types supported for backward compatibility in Oracle type mode".
DOUBLE [PRECISION] or FLOAT[(53)]	BINARY_DOUBLE In Oracle type mode, specify BINARY_DOUBLE . For more information on BINARY_DOUBLE , see "Type specifications".
INT[EGER]	TT_INT[EGER] In Oracle type mode, specify TT_INTEGER . For more information on TT_INTEGER , see "Type specifications".
INTERVAL IntervalQualifier	INTERVAL IntervalQualifier In Oracle type mode, the data type has the same name. For more information on interval types, see"Type specifications".
NCHAR[( n )]	TT_NCHAR[( n )] In Oracle type mode, specify TT_CHAR . For more information on TT_NCHAR , see "Types supported for backward compatibility in Oracle type mode".
NVARCHAR( n )	TT_NVARCHAR( n ) In Oracle type mode, specify TT_NVARCHAR . For more information on TT_NVARCHAR , see "Types supported for backward compatibility in Oracle type mode".
REAL or FLOAT(24)	BINARY_FLOAT In Oracle type mode, specify BINARY_FLOAT . For more information on BINARY_FLOAT , see "Type specifications".
SMALLINT	TT_SMALLINT In Oracle type mode, specify TT_SMALLINT . For more information on TT_SMALLINT , see "Type specifications".
TIME	TIME In Oracle type mode, the data type has the same name. For more information on TIME , see "Type specifications".
TIMESTAMP	TT_TIMESTAMP In Oracle type mode, specify TT_TIMESTAMP . For more information on TT_TIMESTAMP , see "Type specifications".
TINYINT	TT_TINYINT In Oracle type mode, specify TT_TINYINT . For more information on TT_TINYINT , see "Type specifications".
VARBINARY( n )	VARBINARY( n ) In Oracle type mode, the data type has the same name. For more information on VARBINARY( n ) , see"Type specifications".
VARCHAR( n )	TT_VARCHAR( n [BYTE|CHAR]) In Oracle type mode, specify TT_VARCHAR . Character semantics is supported. For more information on TT_VARCHAR , see "Types supported for backward compatibility in Oracle type mode".

Character data
types

Character data types store character (alphanumeric) data either in the database character set or the UTF-16 format. Character data is stored in strings with byte values. The byte values correspond to one of the database character sets defined when the database
is created. TimesTen supports both single and multibyte character sets.

The character types are as follows:

CHAR

NCHAR

VARCHAR2

NVARCHAR2

CHAR

The

CHAR

type specifies a fixed length character string. If you insert a value into a

CHAR

column and the value is shorter than the defined column length, then TimesTen blank-pads the value to the column length. If you insert a value
into a

CHAR

column and the value is longer than the defined length, TimesTen returns an error.

By default, the column length is defined in bytes. Use the

CHAR

qualifier to define the column length in characters. The size of a character ranges from one byte to four bytes depending on the database character set. The

BYTE

and

CHAR

qualifiers
override the

NLS_LENGTH_SEMANTICS

parameter setting. For more information about

NLS_LENGTH_SEMANTICS

, see "ALTER
SESSION" and "Setting globalization support attributes" in Oracle
TimesTen In-Memory Database Operations Guide.

Note:
With the

CHAR

type, a zero-length string is interpreted as

NULL

. With the

TT_CHAR

type, a zero-length string is a valid non-

NULL

value. Both

CHAR

and

TT_CHAR

use blank padded comparison
semantics. The

TT_CHAR

type is supported for backward compatibility.
The following example creates a table. Columns are defined with type

CHAR

and

TT_CHAR

. Blank padded comparison semantics are used for these types.

Command> CREATE TABLE typedemo (name CHAR (20), nnme2 TT_CHAR (20));
Command> INSERT INTO typedemo VALUES ('SMITH     ','SMITH     ');
1 row inserted.
Command> DESCRIBE typedemo;
Table USER.TYPEDEMO:
Columns:
NAME                            CHAR (20)
NAME2                           TT_CHAR (20)
1 table found.
(primary key columns are indicated with *)
Command> SELECT * FROM typedemo;
< SMITH     , SMITH      >
1 row found.
Command> # Expect 1 row found; blank-padded comparison semantics
Command> SELECT * FROM typedemo WHERE name = 'SMITH';
< SMITH     , SMITH      >
1 row found.
Command> SELECT * FROM typedemo WHERE name2 = 'SMITH';
< SMITH     , SMITH      >
1 row found.
Command> # Expect 0 rows; blank padded comparison semantics.
Command> SELECT * FROM typedemo WHERE name > 'SMITH';
0 rows found.
Command> SELECT * FROM typedemo WHERE name2 > 'SMITH';
0 rows found.

The following example alters table

typedemo

adding column

name3

. The column

name3

is defined with character semantics.

Command> ALTER TABLE typedemo ADD COLUMN name3 CHAR (10 CHAR);
Command> DESCRIBE typedemo;
Table USER.TYPEDEMO:
Columns:
NAME                            CHAR (20)
NAME2                           TT_CHAR (20)
NAME3                           CHAR (10 CHAR)
1 table found.

NCHAR

The

NCHAR

data type is a fixed length string of two-byte Unicode characters.

NCHAR

data types are padded to the specified length with the Unicode space character

U+0020 SPACE

. Blank-padded comparison semantics are used.

Note:
With the

NCHAR

type, a zero-length string is interpreted as

NULL

. With the

TT_NCHAR

type, a zero-length string is a valid non-

NULL

value. Both

NCHAR

and

TT_NCHAR

use blank padded comparison
semantics. The

TT_NCHAR

type is supported for backward compatibility.
The following example alters table

typedemo

, adding column

Name4

. Data type is

NCHAR

.

Command> ALTER TABLE typedemo ADD COLUMN Name4 NCHAR (10);
Command> DESCRIBE typedemo;

Table USER.TYPEDEMO:
Columns:
NAME                            CHAR (20)
NAME2                           TT_CHAR (20)
NAME3                           CHAR (10 CHAR)
NAME4                           NCHAR (10)
1 table found.

VARCHAR2

The

VARCHAR2

data type specifies a variable length character string. When you define a

VARCHAR2

column, you define the maximum number of bytes or characters. Each value is stored exactly as you specify it. The value cannot exceed
the maximum length of the column.

You must specify the maximum length. The minimum must be at least one byte. Use the

CHAR

qualifier to specify the maximum length in characters. For example,

VARCHAR2(10 CHAR)

.

The size of a character ranges from one byte to four bytes depending on the database character set. The

BYTE

and

CHAR

qualifiers override the

NLS_LENGTH_SEMANTICS

parameter setting. For more information on

NLS_LENGTH_SEMANTICS

,
see "ALTER SESSION" and "Setting
globalization support attributes" in Oracle TimesTen In-Memory Database Operations Guide.

The

NULL

value is stored as a single bit for each nullable field within the row. A

NOT INLINE VARCHAR2(

n

)

whose value is

NULL

takes
(null bit) + four bytes of storage on 32-bit platforms, whereas an

INLINE VARCHAR2(

n

)

whose value is

NULL

takes (null bit) + four bytes +

n

bytes of storage, or

n

more bytes of storage
than a

NOT INLINE VARCHAR2(

n

)

whose value is

NULL

. This storage principal holds for all variable length data types:

TT_VARCHAR

,

TT_NVARCHAR

,

VARCHAR2

,

NVARCHAR2

,

VARBINARY

.

Notes:

Do not use the

VARCHAR

data type. Use

VARCHAR2

. Even though both data types are currently synonymous, the

VARCHAR

data type may be redefined as a different data type with different semantics.

With the

VARCHAR2

type, a zero-length string is interpreted as

NULL

. With the

TT_VARCHAR

type, a zero-length string is a valid non-NULL value.

VARCHAR2

uses nonpadded comparison semantics.

TT_VARCHAR

uses
blank-padded comparison semantics. The

TT_VARCHAR

type is supported for backward compatibility.

The following example alters table

typedemo

, adding columns

name5

and

name6

. The

name5

column is defined with type

VARCHAR2

. The

name6

column is defined with

TT_VARCHAR

.
The example illustrates the use of nonpadded comparison semantics with column

name5

and blank-padded comparison semantics with column

name6

:

Command> ALTER TABLE typedemo ADD COLUMN name5 VARCHAR2 (20);
Command> ALTER TABLE typedemo ADD COLUMN name6 TT_VARCHAR (20);
Command> DESCRIBE typedemo;
Table USER.TYPEDEMO:
Columns:
NAME                            CHAR (20)
NAME2                           TT_CHAR (20)
NAME3                           CHAR (10 CHAR)
NAME4                           NCHAR (10)
NAME5                           VARCHAR2 (20) INLINE
NAME6                           TT_VARCHAR (20) INLINE
1 table found.
(primary key columns are indicated with *)
Command> #Insert SMITH followed by 5 spaces into all columns
Command> INSERT INTO typedemo VALUES
> ('SMITH     ', 'SMITH     ', 'SMITH     ', 'SMITH     ','SMITH     ',
> 'SMITH');
1 row inserted.
Command> # Expect 0; Nonpadded comparison semantics
Command> SELECT COUNT (*) FROM typedemo WHERE name5 = 'SMITH';
< 0 >
1 row found.
Command> # Expect 1; Blank-padded comparison semantics
Command> SELECT COUNT (*) FROM typedemo WHERE name6 = 'SMITH';
< 1 >
1 row found.
Command> # Expect 1; Nonpadded comparison semantics
Command> SELECT COUNT (*) FROM typedemo WHERE name5 > 'SMITH';
< 1 >
1 row found.
Command> # Expect 0; Blank-padded comparison semantics
Command> SELECT COUNT (*) FROM typedemo WHERE name6 > 'SMITH';
< 0 >
1 row found.

NVARCHAR2

The

NVARCHAR2

data type is a variable length string of two-byte Unicode characters. When you define an

NVARCHAR2

column, you define the maximum number of characters. Each value is stored exactly as you specify it. The value cannot
exceed the maximum length of the column.

Note:
With the

NVARCHAR2

type, a zero-length string is interpreted as

NULL

. With the

TT_NVARCHAR

type, a zero-length string is a valid non-NULL value.

NVARCHAR2

uses nonpadded comparison semantics.

TT_NVARCHAR

uses
blank-padded comparison semantics. The

TT_NVARCHAR

type is supported for backward compatibility.
The following example alters table

typedemo

adding column

name7

. Data type is

NVARCHAR2

.

Command> ALTER TABLE typedemo ADD COLUMN Nnme7 NVARCHAR2 (20);
Command> DESCRIBE typedemo;
Table USER1.TYPEDEMO:
Columns:
NAME                            CHAR (20)
NAME2                           TT_CHAR (20)
NAME3                           CHAR (10 CHAR)
NAME4                           NCHAR (10)
NAME5                           VARCHAR2 (20) INLINE
NAME6                           TT_VARCHAR (20) INLINE
NAME7                           NVARCHAR2 (20) INLINE
1 table found.

Numeric data types

Numeric types store positive and negative fixed and floating-point numbers, zero, infinity, and values that are the undefined result of an operation (

NaN

, meaning
not a number).

TimesTen supports both exact and approximate numeric data types. Arithmetic operations can be performed on numeric types only. Similarly,

SUM

and

AVG

aggregates require numeric types.

The exact numeric types are:

NUMBER

TT_BIGINT

TT_INTEGER

TT_SMALLINT

TT_TINYINT

The approximate types are:

BINARY_DOUBLE

BINARY_FLOAT

FLOAT and FLOAT(n)

NUMBER

The

NUMBER

data type stores zero as well as positive and negative fixed numbers with absolute values from 1.0 x 10-130 up to but not including 1.0 x 10 126. Each

NUMBER

value requires from five to 22 bytes.

Specify a fixed-point number as

NUMBER(

p,s

)

, where the following holds:

The argument

p

is the precision or the total number of significant decimal digits, where the most significant digit is the left-most non-zero digit and the least significant digit is the right-most known digit.

The argument

s

is the scale, or the number of digits from the decimal point to the least significant digit. The scale ranges from -84 to 127.

Positive scale is the number of significant digits to the right of the decimal point up to and including the least significant digit.

Negative scale is the number of significant digits to the left of the decimal point up to but not including the least significant digit. For negative scale, the least significant digit is on the left side of the decimal point, because the number is rounded
to the specified number of places to the left of the decimal point.

Scale can be greater than precision. For example, in the case of E-notation. When scale is greater than precision, the precision specifies the maximum number of significant digits to the right of the decimal point. For example, if you define the column as
type

NUMBER(4,5)

and you insert .000127 into the column, the value is stored as .00013. A zero is required for the first digit after the decimal point. TimesTen rounds values after the fifth digit to the right of the decimal point.

If a value exceeds the precision, then TimesTen returns an error. If a value exceeds the scale, then TimesTen rounds the value.

NUMBER(

p

)

represents a fixed-point number with precision

p

and scale 0 and is equivalent to

NUMBER(

p

,0)

.

Specify a floating-point number as

NUMBER

. If you do not specify precision and scale, TimesTen uses the maximum precision and scale.

The following example alters table

numerics

by adding columns

col6

,

col7

,

col8

, and

col9

defined with the

NUMBER

data type and specified with different precisions and scales.

Command> ALTER TABLE numerics ADD col6 NUMBER;
Command> ALTER TABLE numerics ADD col7 NUMBER (4,2);
Command> ALTER TABLE numerics ADD col8 NUMBER (4,-2);
Command> ALTER TABLE numerics ADD col8 NUMBER (2,4);
Command> ALTER TABLE numerics ADD col9 NUMBER (2,4);
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            TT_SMALLINT
COL3                            TT_INTEGER
COL4                            TT_INTEGER
COL5                            TT_BIGINT
COL6                            NUMBER
COL7                            NUMBER (4,2)
COL8                            NUMBER (4,-2)
COL9                            NUMBER (2,4)
1 table found.
(primary key columns are indicated with *)

The next example creates table

numbercombo

and defines columns with the

NUMBER

data type using different precisions and scales. The value 123.89 is inserted into the columns.

Command> CREATE TABLE numbercombo (col1 NUMBER, col2 NUMBER (3),
> col3 NUMBER (6,2), col4 NUMBER (6,1), col5 NUMBER (6,-2));
Command> DESCRIBE numbercombo;
Table USER1.NUMBERCOMBO:
Columns:
COL1                            NUMBER
COL2                            NUMBER (3)
COL3                            NUMBER (6,2)
COL4                            NUMBER (6,1)
COL5                            NUMBER (6,-2)
1 table found.
(primary key columns are indicated with *)
Command> INSERT INTO numbercombo VALUES (123.89,123.89,123.89,123.89,123.89);
1 row inserted.
Command> VERTICAL ON;
Command> SELECT * FROM numbercombo;
COL1:   123.89
COL2:   124
COL3:   123.89
COL4:   123.9
COL5:   100
1 row found.

The next example creates a table and defines a column with data type

NUMBER(4,2)

. An attempt to insert a value of 123.89 results in an overflow error.

Command> CREATE TABLE invnumbervalue (col6 NUMBER (4,2));
Command> INSERT INTO invnumbervalue VALUES (123.89);
2923: Number type value overflow
The command failed.

The next example creates a table and defines columns with the

NUMBER

data type using a scale that is greater than the precision. Values are inserted into the columns.

Command> CREATE TABLE numbercombo2 (col1 NUMBER (4,5), col2 NUMBER (4,5),
> col3 NUMBER (4,5), col4 NUMBER (2,7), col5 NUMBER (2,7),
> col6 NUMBER (2,5), col7 NUMBER (2,5));
Command> INSERT INTO numbercombo2 VALUES
> (.01234, .00012, .000127, .0000012, .00000123, 1.2e-4, 1.2e-5);
1 row inserted.
Command> DESCRIBE numbercombo2;
Table USER1.NUMBERCOMBO2:
Columns:
COL1                            NUMBER (4,5)
COL2                            NUMBER (4,5)
COL3                            NUMBER (4,5)
COL4                            NUMBER (2,7)
COL5                            NUMBER (2,7)
COL6                            NUMBER (2,5)
COL7                            NUMBER (2,5)
1 table found.

(primary key columns are indicated with *)
Command> SELECT * FROM numbercombo2;
COL1:   .01234
COL2:   .00012
COL3:   .00013
COL4:   .0000012
COL5:   .0000012
COL6:   .00012
COL7:   .00001
1 row found.

TT_BIGINT

The

TT_BIGINT

data type is a signed integer that ranges from -9,223,372,036,854,775,808 (-263) to 9,223,372,036,854,775,807 (263-1). It requires eight bytes of storage and thus is more compact than the

NUMBER

data
type. It also has better performance than the

NUMBER

data type. You cannot specify

BIGINT

.

This example alters table

numerics

and attempts to add

col5

with a data type of

BIGINT

. TimesTen generates an error. A second

ALTER TABLE

successfully adds

col5

with the data type

TT_BIGINT

.

Command> ALTER TABLE numerics ADD COLUMN col5 BIGINT;
3300: BIGINT is not a valid type name; use TT_BIGINT instead
The command failed.
Command> ALTER TABLE numerics ADD COLUMN col5 TT_BIGINT;
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            TT_SMALLINT
COL3                            TT_INTEGER
COL4                            TT_INTEGER
COL5                            TT_BIGINT
1 table found.
(primary key columns are indicated with *)

TT_INTEGER

The

TT_INTEGER

data type is a signed integer that ranges from -2,147,483,648 (-231) to 2,147,483,647 (231 -1). It requires four bytes of storage and thus is more compact than the

NUMBER

data type. It also has
better performance than the

NUMBER

data

type. You can specify

TT_INT

for

TT_INTEGER

. If you specify either

INTEGER

or

INT

, these types are mapped to

NUMBER(38)

.

The following example alters the table

numerics

and adds

col3

with the data type

INT

. Describing the table shows that the data type is

NUMBER(38)

. The column

col3

is dropped. A second

ALTER
TABLE

adds

col2

with the data type

INTEGER

. Describing the table shows that the data type is

NUMBER(38)

. The column

col3

is dropped. Columns

col3

and

col4

are then added with
the data types

TT_INTEGER

and

TT_INT

. Describing the table shows both data types as

TT_INTEGER

.

Command> ALTER TABLE numerics ADD col3 INT;
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            TT_SMALLINT
COL3                            NUMBER (38)
1 table found.
(primary key columns are indicated with *)
Command> ALTER TABLE numerics  col3;
Command> ALTER TABLE numerics ADD col3 INTEGER;
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            TT_SMALLINT
COL3                            NUMBER (38)
1 table found.
(primary key columns are indicated with *)
Command> ALTER TABLE numerics  col3;
Command> ALTER TABLE numerics ADD COLUMN col3 TT_INTEGER;
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            TT_SMALLINT
COL3                            TT_INTEGER
1 table found.
(primary key columns are indicated with *)
Command> ALTER TABLE numerics ADD col4 TT_INT;
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            TT_SMALLINT
COL3                            TT_INTEGER
COL4                            TT_INTEGER
1 table found.
(primary key columns are indicated with *)

TT_SMALLINT

The

TT_SMALLINT

data type is a signed integer that ranges from -32,768 (-215) to 32,767 (215-1). It requires two bytes of storage and thus is more compact than the

NUMBER

data type. It also has better performance
than the

NUMBER

data type. You can specify the data type

SMALLINT

, but it maps to

NUMBER(38)

.

The following example alters the table

numerics

and adds

col2

with the data type

SMALLINT

. Describing the table shows that the data type is

NUMBER(38)

. The column

col2

is dropped. A second

ALTER
TABLE

adds

col2

with the data type

TT_SMALLINT

.

Command> ALTER TABLE numerics ADD COLUMN col2 SMALLINT;
Command> DESCRIBE Numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            NUMBER (38)
1 table found.
(primary key columns are indicated with *)
Command> ALTER TABLE numerics  COLUMN col2;
Command> ALTER TABLE numerics ADD COLUMN col2 TT_SMALLINT;
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
COL2                            TT_SMALLINT
1 table found.
(primary key columns are indicated with *)

TT_TINYINT

The

TT_TINYINT

data type is an unsigned integer that ranges from 0 to 255 (28 -1). It requires one byte of storage and thus is more compact than the

NUMBER

data type. It also has better performance than the

NUMBER

data
type. The data type of a negative

TT_TINYINT

is

TT_SMALLINT

. You cannot specify

TINYINT

.

The following example first attempts to create a table named

numerics

that defines a column named

col1

with data type

TINYINT

. TimesTen returns an error. The example then redefines the column with data type

TT_TINYINT

.

Command> CREATE TABLE numerics (col1 TINYINT);
3300: TINYINT is not a valid type name; use TT_TINYINT instead
The command failed.
Command> CREATE TABLE numerics (col1 TT_TINYINT);
Command> DESCRIBE numerics;
Table USER1.NUMERICS:
Columns:
COL1                            TT_TINYINT
1 table found.
(primary key columns are indicated with *)

Floating-point numbers

Floating-point numbers can be with or without a decimal point. An exponent may be used to increase the range (for example, 1.2E-20).

Floating-point numbers do not have a scale because the number of digits that can appear after the decimal point is not restricted.

Binary floating-point numbers are stored using binary precision (the digits 0 and 1). For the

NUMBER

data type, values are stored using decimal precision (the digits 0 through 9).

Literal values that are within the range and precision supported by

NUMBER

are stored as

NUMBER

because literals are expressed using decimal precision.

Use one of the following data types for floating-point numbers:

BINARY_DOUBLE

BINARY_FLOAT

FLOAT and FLOAT(n)

BINARY_DOUBLE

BINARY_DOUBLE

is a 64-bit, double-precision, floating-point number.

Both

BINARY_FLOAT

and

BINARY_DOUBLE

support the special values

Inf

,

-Inf

, and

NaN

(not a number) and conform to the IEEE standard.

Floating-point number limits:

BINARY_FLOAT

Minimum positive finite value: 1.17549E-38F

Maximum positive finite value: 3.40282E+38F

BINARY_DOUBLE

Minimum positive finite value: 2.22507485850720E-308

Maximum positive finite value: 1.79769313486231E+308

The following example creates a table and defines two columns with the

BINARY_FLOAT

and

BINARY_DOUBLE

data types.

Command> CREATE TABLE BfBd (Col1 BINARY_FLOAT, Col2 BINARY_DOUBLE);
Command> DESCRIBE BfBd;
Table UISER1.BFBD:
Columns:
COL1                            BINARY_FLOAT
COL2                            BINARY_DOUBLE
1 table found.
(primary key columns are indicated with *)

BINARY_FLOAT

BINARY_FLOAT

is a 32-bit, single-precision, floating-point number.

FLOAT
and FLOAT(n)

TimesTen also supports the ANSI type

FLOAT

.

FLOAT

is an exact numeric type and is implemented as the

NUMBER

type. The value of

n

indicates the number of bits of precision that can be stored, from 1 to 126.
To convert from binary precision to decimal precision, multiply

n

by 0.30103. To convert from decimal precision to binary precision, multiply the decimal precision by 3.32193. The maximum 126 digits of binary precision is equivalent to approximately
38 digits of decimal precision.

BINARY
and VARBINARY data types

The

BINARY

data type is a fixed-length binary value with a length of

n

bytes, where the value of

n

ranges from 1 to 8300 bytes. The

BINARY

data type requires

n

bytes of storage. Data is padded
to the maximum column size with trailing zeros. Zero padded comparison semantics are used.

The

VARBINARY

data type is a variable-length binary value having a maximum length of

n

bytes, where the value of

n

ranges from 1 to 4,194,304 (222) bytes.

The following example creates a table and defines two columns:

col1

is defined with data type

BINARY

and

col2

with data type

VARBINARY

. Then, binary data is inserted into each column. Note that the

BINARY

value
is padded to the right with zeros.

Note:
For details on assigning hexadecimal literals as binary data in TimesTen, see the description for the

HexadecimalLiteral

in "Constants".

Command> CREATE TABLE bvar (col1 BINARY (10), col2 VARBINARY (10));
Command> DESCRIBE bvar;
Table USER1.BVAR:
Columns:
COL1                            BINARY (10)
COL2                            VARBINARY (10) INLINE
1 table found.
(primary key columns are indicated with *)

Command> INSERT INTO bvar (col1, col2)
> VALUES (0x4D7953514C, 0x39274D);
1 row inserted.

Command> select * from bvar;
< 4D7953514C0000000000, 39274D >
1 row found.

Numeric precedence

The result type of an expression is determined by the operand with the highest type precedence. The numeric precedence order is as follows (highest to lowest):

BINARY_DOUBLE

BINARY_FLOAT

NUMBER

TT_BIGINT

TT_INTEGER

TT_SMALLINT

TT_TINYINT

For example, the sum of

TT_INTEGER

and

BINARY_FLOAT

values is type

BINARY_FLOAT

because

BINARY_FLOAT

has higher numeric precedence. Similarly, the product of

NUMBER

and

BINARY_DOUBLE

values
is type

BINARY_DOUBLE

.

LOB data types

The large object (LOB) data types can store large and unstructured data such as text, image, video, and spatial data. LOBs include the

BLOB

,

CLOB

and

NCLOB

data types.

You can insert or update data in a column that is of a LOB data type. For update operations, you can set the LOB value to

NULL

, an empty value through

EMPTY_CLOB

or

EMPTY_BLOB

, or replace the entire LOB with new data.
You can update a LOB value with another LOB value. If you delete a row containing a LOB column, you also delete the LOB value.

LOB data type semantics are similar to the following SQL semantics:

BLOB

data types use SQL

VARBINARY

semantics.

CLOB

data types use SQL

VARCHAR2

semantics.

NCLOB

data types use SQL

NVARCHAR2

semantics.

The following SQL statements, operators, and functions accept one or more of the LOB data types as arguments.

SQL statements:

CREATE TABLE

,

SELECT

,

INSERT

, and

UPDATE

.

Operators:

LIKE

and

IS [NOT] NULL

.

Functions:

ASCIISTR

,

CONCAT

,

INSTR

,

INSTRB

,

INSTR4

,

LENGTH

,

LENGTHB

,

LOWER

,

LPAD

,

NLSSORT

,

NVL

,

TRIM

,

LTRIM

,

RTRIM

,

SUBSTR

,

SUBSTRB

,

SUBSTR4

,

REPLACE

,

RPAD

,

SOUNDEX

,

TO_DATE

,

TO_NUMBER

,

TO_CHAR

,
and

UPPER

.

Note:
Support for LOB data types are detailed in the appropriate SQL operator, statement and function documentation.
Description

LOB conversion SQL functions (TO_BLOB,TO_CLOB,
and TO_LOB) convert to the desired LOB data type.

LOB columns are always stored out of line, so you cannot use the

INLINE

attribute when declaring LOB columns.

You can define multiple columns of the LOB data type within a single table.

You cannot create a primary key, unique index, or unique constraint on LOB columns.

You cannot create a materialized view if the detail table contains a LOB column.

In addition to SQL, you can use LOB specific APIs in PL/SQL, ODBC, JDBC, OCI, and PRO*C/C++ for creating and updating LOBs. See the appropriate TimesTen developer's guide for more information on these APIs.

The following sections describe each LOB data type in more detail:

BLOB

CLOB

NCLOB

In addition, the following sections provide more details on LOBs in general:

Difference between NULL and empty LOBs

Initializing LOBs

BLOB

The Binary LOB (

BLOB

) data type stores unstructured binary large objects. The maximum size for

BLOB

data is 16 MB.

Note:
For details on assigning hexadecimal literals as binary data in TimesTen, see the description for the

HexadecimalLiteral

in "Constants".
When you define a

BLOB

in a column, you do not define the maximum number of characters as you would with

VARBINARY

and other variable length data types. Instead, the definition for the column would be as follows:

Command> CREATE TABLE blob_content (
> id NUMBER PRIMARY KEY,
> blob_column BLOB );

To manipulate a

BLOB

, the following functions are provided:

There are two methods to initialize a

BLOB

, including the

EMPTY_BLOB

function to initialize an empty

BLOB

. For details on initializing a

BLOB

, see "Initializing
LOBs". For details on how an empty LOB is different from a

NULL

LOB, see "Difference between
NULL and empty LOBs".

To convert a binary value to a

BLOB

, use the

TO_LOB

or

TO_BLOB

functions. See "TO_BLOB" and "TO_LOB"for
more details.

CLOB

The Character LOB (

CLOB

) data type stores single-byte and multibyte character data. The maximum size for

CLOB

data is 4 MB. The maximum number of characters that can be stored in the

CLOB

depends on whether you are using
a single or multibyte character set.

When you define a

CLOB

in a column, you do not define the maximum number of characters as you would with

VARCHAR

and other variable length data types. Instead, the definition for the column would be as follows:

Command> CREATE TABLE clob_content (
> id NUMBER PRIMARY KEY,
> clob_column CLOB );

To manipulate a

CLOB

, the following functions are provided:

There are two methods to initialize a

CLOB

, including the

EMPTY_CLOB

function to initialize an empty

CLOB

. For details on initializing a

CLOB

, see "Initializing
LOBs". For details on how an empty LOB is different from a

NULL

LOB, see "Difference between
NULL and empty LOBs".

To convert a character string to a

CLOB

, use the

TO_LOB

or

TO_CLOB

functions. See "TO_CLOB" and"TO_LOB" for
more details.

NCLOB

The National Character LOB (

NCLOB

) data type stores Unicode data. The maximum size for an

NCLOB

data is 4 MB.

When you define a

NCLOB

in a column, you do not define the maximum number of characters as you would with

VARCHAR

and other variable length data types. Instead, the definition for the column would be as follows:

Command> CREATE TABLE nclob_content (
> id NUMBER PRIMARY KEY,
> nclob_column NCLOB );

The following functions support the

NCLOB

data type:

There are two methods to initialize an

NCLOB

, including the

EMPTY_CLOB

function to initialize an empty

NCLOB

. For details on initializing a

NCLOB

, see "Initializing
LOBs". For details on how an empty LOB is different from a

NULL

LOB, see "Difference between
NULL and empty LOBs".

To convert a character string to an

NCLOB

, use the

TO_LOB

or

TO_CLOB

functions. See "TO_CLOB" and"TO_LOB" for
more details.

Difference between NULL and empty LOBs

A

NULL

LOB is not the same as an empty LOB.

A

NULL

LOB has the value of

NULL

, so

NULL

is returned if you request a

NULL

LOB.

An empty LOB is initialized with either the

EMPTY_CLOB

or

EMPTY_BLOB

functions. These functions initialize the LOB to be a zero-length, non-

NULL

value. You can also use the

EMPTY_CLOB

or

EMPTY_BLOB

functions
to initialize a LOB in a non-nullable column.

Initializing LOBs

You can initialize a LOB in one of two ways:

You can insert an empty LOB into a

BLOB

,

CLOB

or

NCLOB

column by using the

EMPTY_BLOB

or

EMPTY_CLOB

functions. This is useful when you do not have any data, but want to create the LOB in preparation
for data. It is also useful for initializing non-nullable LOB columns.

Initialize the LOB by inserting data directly. There is no need to initialize a LOB using the

EMPTY_BLOB

or

EMPTY_CLOB

functions, you can simply insert the data directly.

The following demonstrates examples of each type of initialization:

You can initialize a LOB with the

EMPTY_CLOB

function, as shown with the following example:

Command> INSERT INTO clob_content (id, clob_column)
> VALUES (1, EMPTY_CLOB( ) );
1 row inserted.

You can initialize a LOB by inserting data directly, as shown with the following example:

Command> INSERT INTO clob_content(id, clob_column)
> VALUES (4, 'Demonstration of the LOB initialization.');
1 row inserted.

You can initialize or update an existing LOB value with the

UPDATE

statement, as shown with the following examples:

Command> UPDATE blob_content
> SET blob_column = 0x000AF4511
> WHERE id = 1;
1 row updated.

Command> select * from blob_content;
< 1, 0000AF4511 >
1 rows found.

Command> UPDATE clob_content
> SET clob_column = 'Demonstration of the CLOB data type '
> WHERE id = 1;
1 row updated.

Command> SELECT * FROM clob_content;
< 1, Demonstration of the CLOB data type >

ROWID data type

The address of a row in a table or materialized view is called arowid.
The rowid data type is

ROWID

. You can examine a rowid by querying the

ROWID

pseudocolumn. See "ROWID" for
details on the

ROWID

pseudocolumn.

Specify literal

ROWID

values in SQL statements as constants enclosed in single quotes, as follows:

Command> SELECT ROWID, last_name
> FROM employees
> WHERE department_id = 20;

< BMUFVUAAACOAAAALhM, Hartstein >
< BMUFVUAAACOAAAAMhM, Fay >
2 rows found.

Command> SELECT ROWID, last_name FROM employees
> WHERE ROWID='BMUFVUAAACOAAAALhM';
< BMUFVUAAACOAAAALhM, Hartstein >
1 row found.

The

ROWID

data type can be used as follows:

As the data type for a table column or materialized view column

In these types of expressions:

Literals

Comparisons:

<

,

<=

,

>

,

>=

,

BETWEEN

CASE expressions

CAST

COALESCE

COUNT

DECODE

GREATEST

IN

IS NULL

LEAST

MAX

MIN

NVL

TO_CHAR

TT_HASH

In

ORDER BY

and

GROUP BY

clauses

In

INSERT...SELECT

statements. Column

col1

has been defined with the

ROWID

data type for these examples:

Command> DESCRIBE master;

Table MYUSER.MASTER:
Columns:
*ID                              ROWID NOT NULL
NAME                            CHAR (30)

1 table found.
(primary key columns are indicated with *)

Command> INSERT INTO master(id, name) SELECT ROWID, last_name FROM employees;
107 rows inserted.
Command> SELECT * FROM master;
< BMUFVUAAACOAAAAGhG, King                           >
< BMUFVUAAACOAAAAHhG, Kochhar                        >
< BMUFVUAAACOAAAAIhG, De Haan                        >
...
107 rows found.

You can use the

TO_CHAR

function with the

ROWID

pseudocolumn as shown below:

Command> INSERT INTO master(id, name)
> SELECT TO_CHAR(ROWID), last_name FROM employees;
107 rows inserted.
Command> SELECT * FROM master;
< BMUFVUAAACOAAAAGhG, King                           >
< BMUFVUAAACOAAAAHhG, Kochhar                        >
...
107 rows found.

You can use the

CAST

function with the

ROWID

pseudocolumn as shown below:

Command> CREATE TABLE master (id CHAR(20) NOT NULL PRIMARY KEY,
> name CHAR(30));
Command> INSERT INTO master(id, name) SELECT CAST(ROWID AS CHAR(20)),
> last_name from employees;
107 rows inserted.

Implicit type conversions are supported for assigning values and comparison operations
between

ROWID

and

CHAR

or between

ROWID

and

VARCHAR2

data.

When

CHAR

,

VARCHAR2

, and

ROWID

operands are combined in

COALESCE

,

DECODE

,

NVL

,
or

CASE expressions

, the result data type is

ROWID

. Expressions with

CHAR

and

VARCHAR2

values
are converted to

ROWID

values to evaluate the expression.

To use

ROWID

values with string functions such as

CONCAT

, the application
must convert

ROWID

values explicitly to

CHAR

values using the SQL

TO_CHAR

function.

Datetime data types

The datetime data types are as follows:

DATE

TIME

TIMESTAMP

TT_DATE

TT_TIMESTAMP

DATE

The format of a

DATE

value is

YYYY-MM-DD HH:MI:SS

and ranges from -4712-01-01 (January 1, 4712 BC) to 9999-12-31 (December 31, 9999 AD). There are no fractional seconds. The

DATE

type requires seven bytes of storage.

TimesTen does not support user-specified

NLS_DATE_FORMAT

settings. The SQL

TO_CHAR

and

TO_DATE

functions
can be used to specify other formats.

TIME

The format of a

TIME

value is

HH:MI:SS

and ranges from 00:00:00 (midnight) to 23:59:59 (11:59:59 pm). The

TIME

data type requires eight bytes of storage.

TIMESTAMP

The format of a

TIMESTAMP

value is

YYYY-MM-DD HH:MI:SS [.FFFFFFFFF]

. The fractional seconds precision range is 0 to 9. The default is 6. The date range is from -4712-01-01 (January 1, 4712 BC) to 9999-12-31 (December 31, 9999 AD).
The

TIMESTAMP

type requires 12 bytes of storage. The

TIMESTAMP

type has a larger date range and supports more precision than

TT_TIMESTAMP

.

TimesTen does not support user-specified

NLS_TIMESTAMP_FORMAT

settings. The SQL

TO_CHAR

and

TO_DATE

functions
can be used to specify other formats.

TT_DATE

The format of a

TT_DATE

value is

YYYY-MM-DD

and ranges from 1753-01-01 (January 1, 1753 AD) to 9999-12-31 (December 31, 9999 AD). The

TT_DATE

data type requires four bytes of storage.

TT_TIMESTAMP

The format of a

TT_TIMESTAMP

value is

YYYY-MM-DD HH:MI:SS [.FFFFFFFFF]

. The fractional seconds precision is 6. The range is from 1753-01-01 00:00:00 (January 1, 1753, midnight) to 9999-12-31 23:59:59 (December 31, 9999, 11:59:59
PM). The

TT_TIMESTAMP

type requires eight bytes of storage.

TT_TIMESTAMP

is faster than the

TIMESTAMP

data type and has a smaller storage size.

TimesTen intervals

This section includes the following topics:

Using interval data types

Using DATE and TIME data types

Handling timezone conversions

Datetime and interval data types in arithmetic operations

Using interval data types

If you are using TimesTen type mode, refer to the Oracle TimesTen In-Memory Database API and SQL Reference Guide, Release 6.0.3, for information on interval types.

TimesTen supports interval types only in a constant specification or intermediate expression result. Interval types cannot be the final result. Columns cannot be defined with an interval type. See"Type
specifications".

You can specify a single-field literal that is an interval in an expression, but you cannot specify a complete expression that returns an interval data type. Instead, the

EXTRACT

function
must be used to extract the desired component of the interval result.

TimesTen supports interval literals of the following form:

INTERVAL [+/-]

CharString

IntervalQualifier

Using
DATE and TIME data types

This section shows some

DATE

,

TIME

,
and

TIMESTAMP

data type examples:

To create a table named

sample

that contains a column

dcol

of type

DATE

and a column

tcol

of type

TIME

, use the following:

CREATE TABLE sample (tcol TIME, dcol DATE);

To insert

DATE

and

TIME

values into the

sample

table, use this:

INSERT INTO sample VALUES (TIME '12:00:00', DATE '1998-10-28');

To select all rows in the

sample

table that are between noon and 4:00 p.m. on October 29, 1998, use the following:

SELECT * FROM sample WHERE dcol = DATE '1998-10-29'
AND tcol BETWEEN TIME '12:00:00' AND TIME '16:00:00';

To create a table named

sample2

that contains a column

tscol

of type

TIMESTAMP

and then select all rows in the table that are between noon and 4:00 p.m. on October 29, 1998, use these statements:

CREATE TABLE sample2 (tscol TIMESTAMP);
INSERT INTO sample2 VALUES (TIMESTAMP '1998-10-28 12:00:00');
SELECT * FROM sample2 WHERE tscol
BETWEEN TIMESTAMP '1998-10-29 12:00:00' AND '1998-10-29 16:00:00';

Note:
TimesTen enables both literal and string formats of the

TIME

,

DATE

, and

TIMESTAMP

types. For example,

timestring ('12:00:00')

and

timeliteral (TIME '16:00:00')

are both valid ways to specify a

TIME

value.
TimesTen reads the first value as

CHAR

type and later converts it to

TIME

type as needed. TimesTen reads the second value as

TIME

. The examples above use the literal format. Any values for the fraction not specified in
full microseconds result in a "

Data truncated

" error.

Handling timezone conversions

TimesTen does not support

TIMEZONE

.

TIME

and

TIMESTAMP

data type values are stored without making any adjustment for time difference.
Applications must assume one time zone and convert

TIME

and

TIMESTAMP

to that time zone before sending values to the database. For example, an application can assume its time zone to be Pacific Standard Time. If the application is
using

TIME

and

TIMESTAMP

values from Pacific Daylight Time or Eastern Standard Time, for example, the application must convert

TIME

and

TIMESTAMP

to Pacific Standard Time.

Datetime and interval data types in arithmetic
operations

If you are using TimesTen type mode, see Oracle TimesTen In-Memory Database API and SQL Reference Guide, Release 6.0.3, for information about datetime and interval types in arithmetic operations

You can perform numeric operations on date, timestamp and interval data. TimesTen calculates the results based on the rules:

You can add or subtract a numeric value to or from a

ORA_DATE

or

ORA_TIMESTAMP

value. TimesTen internally converts

ORA_TIMESTAMP

values to

ORA_DATE

values.

You can add or subtract a numeric value to or from a

TT_DATE

or

TT_TIMESTAMP

value and the resulting value is

TT_DATE

or

TT_TIMESTAMP

respectively.

Numeric values are treated as number of days. For example,

SYSDATE

+ 1 is tomorrow.

SYSDATE

- 7 is one week ago.

Subtracting two date columns results in the number of days between the two dates. The return type is numeric.

You cannot add date values. You cannot multiple or divide date or timestamp values.

Table 1-5 is a matrix of datetime arithmetic operations. Dashes represent operations that are not
supported. The matrix assumes that you are using Oracle type mode:

Table
1-5 DateTime arithmetic operations

	DATE	TT_DATE	TIMESTAMP	TT_TIMESTAMP	NUMERIC	INTERVAL
DATE
+ (plus)	—	—	—	—	DATE	DATE
- (minus)	NUMBER	NUMBER	INTERVAL	INTERVAL	DATE	DATE
* (multiply)	—	—	—	—	—	—
/ (divide)	—	—	—	—	—	—
TT_DATE
+ (plus)	—	—	—	—	TT_DATE	TT_DATE
- (minus)	NUMBER	TT_BIGINT	INTERVAL	INTERVAL	TT_DATE	TT_DATE
* (multiply)	—	—	—	—	—	—
/ (divide)	—	—	—	—	—	—
TIMESTAMP
+ (plus)	—	—	—	—	DATE	TIMESTAMP
- (minus)	INTERVAL	INTERVAL	INTERVAL	INTERVAL	DATE	TIMESTAMP
* (multiply)	—	—	—	—	—	—
/ (divide)	—	—	—	—	—	—
TT_TIMESTAMP
+ (plus)	—	—	—	—	TT_TIMESTAMP	TT_TIMESTAMP
- (minus)	INTERVAL	INTERVAL	INTERVAL	INTERVAL	TT_TIMESTAMP	TT_TIMESTAMP
* (multiply)	—	—	—	—	—	—
/ (divide)	—	—	—	—	—	—
NUMERIC
+ (plus)	DATE	TT_DATE	DATE	TT_TIMESTAMP	Not applicable	—
- (minus)	—	—	—	—	Not applicable	—
* (multiply)	—	—	—	—	Not applicable	INTERVAL
/ (divide)	—	—	—	—	Not applicable	—
INTERVAL
+ (plus)	DATE	TT_DATE	TIMESTAMP	TT_TIMESTAMP	—	INTERVAL
- (minus)	—	—		—	—	INTERVAL
* (multiply)	—	—	—	—	INTERVAL	—
/ (divide)	—	—	—	—	INTERVAL	—

Note:
An interval data type cannot be the final result of a complete expression. The

EXTRACT

function
must be used to extract the desired component of this interval result.

SELECT tt_date1 - tt_date2 FROM t1;
SELECT EXTRACT(DAY FROM timestamp1-timestamp2) FROM t1;
SELECT * FROM t1 WHERE timestamp1 - timestamp2 = NUMTODSINTERVAL(10, 'DAY');
SELECT SYSDATE + NUMTODSINTERVAL(20,'SECOND') FROM dual;
SELECT EXTRACT (SECOND FROM timestamp1-timestamp2) FROM dual;
/* select the microsecond difference between two timestamp values d1 and d2 */
SELECT 1000000*(EXTRACT(DAY FROM d1-d2)*24*3600+
EXTRACT(HOUR FROM d1-d2)*3600+
EXTRACT(MINUTE FROM d1-d2)*60+EXTRACT(SECOND FROM d1-d2) FROM d1;

This example inserts

TIMESTAMP

values into two columns and then subtracts the two values using the

EXTRACT

function:

Command> CREATE TABLE ts (id TIMESTAMP, id2 TIMESTAMP);
Command> INSERT INTO ts VALUES (TIMESTAMP '2007-01-20 12:45:23',
> TIMESTAMP '2006-12-25 17:34:22');
1 row inserted.
Command> SELECT EXTRACT (DAY FROM id - id2) FROM ts;
< 25 >
1 row found.

The following queries return errors. You cannot select an interval result:

SELECT timestamp1 - timestamp2 FROM t1;

You cannot compare an

INTERVAL YEAR TO MONTH

with an

INTERVAL DAY TO SECOND

:

SELECT * FROM t1 WHERE timestamp1 - timestamp2 = NUMTOYMINTERVAL(10, 'YEAR');

You cannot compare an

INTERVAL DAY TO SECOND

with an

INTERVAL DAY

:

SELECT * FROM t1 WHERE timestamp1 - timestamp2 = INTERVAL '10' DAY;

You cannot extract

YEAR

from an

INTERVAL DAY TO SECOND

:

SELECT EXTRACT (YEAR FROM timestamp1 - timestamp2) FROM dual;

Restrictions on datetime and interval arithmetic operations

Consider these restrictions when performing datetime and interval arithmetic:

The results for addition and subtraction with

DATE

and

TIMESTAMP

types for

INTERVAL YEAR

and

INTERVAL MONTH

are not closed. For example, adding one year to the

DATE

or

TIMESTAMP

of
'2004-02-29' results in a date arithmetic error (TimesTen error 2787) because February 29, 2005 does not exist (2005 is not a leap year). Adding

INTERVAL '1'

month to

DATE '2005-01-30'

also results in the same error because February
never has 30 days.

The results are closed for

INTERVAL DAY

.

An interval data type cannot be the final result of a complete expression. The

EXTRACT

function
must be used to extract the desired component of the interval result.

Storage
requirements

Variable-length columns whose declared column length is greater than 128 bytes are stored out of line. Variable-length columns whose declared column length is less than or equal to 128 bytes are stored inline. All LOB data types are stored out of line.

For character semantics, the number of bytes stored out of line is dependent on the character set. For example, for a character set with four bytes per character, variable-length columns whose declared column length is greater than 32 (128/4) are stored
out of line.

Table 1-6 shows thestorage
requirements of the various data types.

Table
1-6 Data type storage requirements

Type	Storage required
BINARY( n )	n bytes.
BINARY_DOUBLE	Eight bytes.
BINARY_FLOAT	Four bytes.
CHAR( n [BYTE|CHAR])	n bytes or, if character semantics, n characters. If character semantics, the length of the column ( n ) is based on length semantics and character set.
DATE	Seven bytes.
Interval	An interval type cannot be stored in TimesTen.
NCHAR( n )	Bytes required is 2* n where n is the number of characters.
NUMBER	Five to 22 bytes.
NVARCHAR2( n )	For NOT INLINE columns: On 32-bit platforms, 2*(length of value) + 20 bytes (minimum of 28 bytes). On 64-bit platforms, 2*(length of value) + 24 bytes (minimum of 40 bytes). For INLINE columns: On 32-bit platforms, 2*(length of column) + 4 bytes. On 64-bit platforms, 2*(length of column) + 8 bytes.
ROWID	Twelve bytes.
TIMESTAMP	Twelve bytes.
TT_BIGINT	Eight bytes.
TT_DATE	Four bytes.
TT_DECIMAL( p,s )	Approximately p /2 bytes.
TT_INT[EGER ]	Four bytes.
TT_SMALLINT	Two bytes.
TT_TIME	Eight bytes.
TT_TIMESTAMP	Eight bytes.
TT_TINYINT	One byte.
VARBINARY( n )	For NOT INLINE columns: On 32-bit platforms, length of value + 20 bytes (minimum of 28 bytes). On 64-bit platforms, length of value + 24 bytes (minimum of 40 bytes). For INLINE columns: On 32-bit platforms, length of column + 4 bytes. On 64-bit platforms, length of column + 8 bytes.
VARCHAR2( n [BYTE|CHAR])	For NOT INLINE columns: On 32-bit platforms, length of value + 20 bytes (minimum of 28 bytes). NULL value is stored as (null bit) + 4 bytes, or 4.125 bytes. On 64-bit platforms, length of value + 24 bytes (minimum of 40 bytes). NULL value is stored as (null bit) + 8 bytes, or 8.125 bytes. This storage principal holds for all variable length NOT INLINE data types: TT_VARCHAR , TT_NVARCHAR , VARCHAR2 , NVARCHAR2 , and VARBINARY . For INLINE columns: On 32-bit platforms, n + 4 bytes. NULL value is stored as (null bit) + n + 4 bytes. On 64-bit platforms, n + 8 bytes. NULL value is stored as (null bit) + n + 8 bytes. If character semantics, the length of the column ( n ) is based on length semantics and character set.
BLOB and CLOB	On 32-bit platforms, length of value + 36 bytes (minimum of 40 bytes). On 64-bit platforms, length of value + 48 bytes (minimum of 56 bytes).
NCLOB	On 32-bit platforms, 2 * (length of value) + 36 bytes (minimum of 40 bytes). On 64-bit platforms, 2 * (length of value) + 48 bytes (minimum of 56 bytes).

Data type comparison rules

This section describes how values of each data type are compared in TimesTen.

Numeric values

A larger value is greater than a smaller value: -1 is less than 10, and -10 is less than -1.

The floating-point value

NaN

is greater than any other numeric value and is equal to itself.

Date values

A later date is considered greater than an earlier one. For example, the date equivalent of '10-AUG-2005' is less than that of '30-AUG-2006', and '30-AUG-2006 1:15 pm' is greater than '30-AUG-2006 10:10 am'.

Character values

Character values are compared in the following ways:

Binary and linguistic sorting

Blank-padded and nonpadded comparison semantics

Binary and linguistic sorting

In binary sorting, TimesTen compares character strings according to the concatenated value of the numeric codes of the characters in the database character set. One character is greater than the other if it has a greater numeric values than the other in
the character set. Blanks are less than any character.

Linguistic sorting is useful if the binary sequence of numeric codes does not match the linguistic sequence of the characters you are comparing. In linguistic sorting, SQL sorting and comparison are based on the linguistic rule set by

NLS_SORT

.
For more information on linguistic sorts, see "Linguistic sorts" in Oracle
TimesTen In-Memory Database Operations Guide.

The default is binary sorting.

Blank-padded and nonpadded comparison semantics

With blank-padded semantics, if two values have different lengths, TimesTen adds blanks to the shorter value until both lengths are equal. Values are then compared character by character up to the first character that differs. The value with the greater
character in the first differing position is considered greater. If two values have no differing characters, then they are considered equal. Thus, two values are considered equal if they differ only in the number of trailing blanks.

Blank-padded semantics are used when both values in the comparison are expressions of type

CHAR

or

NCHAR

or text literals.

With nonpadded semantics, two values are compared, character by character, up to the first character that differs. The value with the greater character in that position is considered greater. If two values that have differing lengths are identical up to
the end of the shorter one, then the longer one is considered greater. If two values of equal length have no differing characters, they are considered equal.

Nonpadded semantics are used when both values in the comparison have the type

VARCHAR2

or

NVARCHAR2

.

An example with blank-padded semantics:

'a   ' = 'a'

An example with nonpadded semantics:

'a   ' > 'a'

Data type conversion

Generally an expression cannot contain values of different data types. However, TimesTen supports both implicit and explicit conversion from one data type to another. Because algorithms for implicit conversion are subject to change across software releases
and the behavior of explicit conversions is more predictable, TimesTen recommends explicit conversion.

Implicit data type conversion

TimesTen converts a value from one data type to another when such a conversion makes sense.

Table 1-7 andTable
1-8 use a matrix to illustrate TimesTen implicit data type conversions.

YES

in the cell indicates the conversion is supported.

NO

in the cell indicates the conversion is not supported. The rules for implicit conversion follow the
table.

Table
1-7 Implicit data type conversion

	CHAR	VARCHAR2	NCHAR	NVARCHAR2	DATE	TT_DATE	TIMESTAMP	TT_TIMESTAMP
CHAR	—	YES	YES	YES	YES	YES	YES	YES
VARCHAR2	YES	—	YES	YES	YES	YES	YES	YES
NCHAR	YES	YES	—	YES	YES	YES	YES	YES
NVARCHAR2	YES	YES	YES	—	YES	YES	YES	YES
DATE	YES	YES	YES	YES	—	YES	YES	YES
TT_DATE	YES	YES	YES	YES	YES	—	YES	YES
TIMESTAMP	YES	YES	YES	YES	YES	YES	—	YES
TT_TIMESTAMP	YES	YES	YES	YES	YES	YES	YES	—
NUMERIC	YES	YES	YES	YES	NO	NO	NO	NO
BLOB	NO	NO	NO	NO	NO	NO	NO	NO
CLOB	YES	YES	YES	YES	NO	NO	NO	NO
NCLOB	YES	YES	YES	YES	NO	NO	NO	NO
BINARY/VARBINARY	YES	YES	YES	YES	NO	NO	NO	NO
ROWID	YES	YES	YES	YES	NO	NO	NO	NO

Table
1-8 Implict data type conversion (continued)

	NUMERIC	BLOB	CLOB	NCLOB	BINARY/VARBINARY	ROWID
CHAR	YES	YES	YES	YES	YES	YES
VARCHAR2	YES	YES	YES	YES	YES	YES
NCHAR	YES	YES	YES	YES	YES	YES
NVARCHAR2	YES	YES	YES	YES	YES	YES
DATE	NO	NO	NO	NO	NO	NO
TT_DATE	NO	NO	NO	NO	NO	NO
TIMESTAMP	NO	NO	NO	NO	NO	NO
TT_TIMESTAMP	NO	NO	NO	NO	NO	NO
NUMERIC	—	NO	NO	NO	NO	NO
BLOB	NO	—	NO	NO	YES	NO
CLOB	NO	NO	—	YES	NO	NO
NCLOB	NO	NO	YES	—	NO	NO
BINARY/VARBINARY	NO	YES	YES	YES	—	NO
ROWID	NO	NO	NO	NO	NO	—

The following rules apply:

During arithmetic operations on and comparisons between character and non-character data types, TimesTen converts from any character data type to a numeric or datetime data type as appropriate. In arithmetic operations between

CHAR

/

VARCHAR2

and

NCHAR

/

NVARCHAR2

,
TimesTen converts to a

NUMBER

.

During arithmetic operations, floating point values

INF

and

NAN

are not supported when converting character values to numeric values.

During concatenation operations, TimesTen converts non-character data types to

CHAR

,

NCHAR

,

VARCHAR2

, or

NVARCHAR2

depending on the other operand.

When comparing a character value with a numeric value, TimesTen converts the character data to a numeric value.

When comparing a character value with a datetime value, TimesTen converts the character data to a datetime value.

During conversion from a timestamp value to a

DATE

value, the fractional seconds portion of the timestamp value is truncated.

Conversions from

BINARY_FLOAT

to

BINARY_DOUBLE

are exact.

Conversions from

BINARY_DOUBLE

to

BINARY_FLOAT

are inexact if the

BINARY_DOUBLE

value uses more bits of precision that supported by the

BINARY_FLOAT

.

Conversions between either character values or exact numeric values (

TT_TINYINT

,

TT_SMALLINT

,

TT_INTEGER

,

TT_BIGINT

,

NUMBER

) and floating-point values (

BINARY_FLOAT

,

BINARY_DOUBLE

)
can be inexact because the character values and the exact numeric values use decimal precision whereas the floating-point numbers use binary precision.

When manipulating numeric values, TimesTen usually adjusts precision and scale to allow for maximum capacity. In such cases, the numeric data type resulting from such operations can differ from the numeric data type found in the underlying tables.

When making assignments, TimesTen converts the value on the right side of the equal sign (=) to the data type of the target of the assignment on the left side.

When you use a SQL function or operator with an argument of a data type other than the one it accepts, TimesTen converts the argument to the accepted data type so long as TimesTen supports the implicit conversion. For more information on supported data type
conversions, see Implicit data type conversion.

During

INSERT

,

INSERT... SELECT

, and

UPDATE

operations, TimesTen converts the value to the data type of the affected column.

Implicit and explicit

CHAR

/

VARCHAR2

<->

NCHAR

/

NVARCHAR

2 conversions are supported except when the character set is

TIMESTEN8

. An example of implicit conversion:

Command> CREATE TABLE convdemo (c1 CHAR (10), x1 TT_INTEGER);
Command> CREATE TABLE convdemo2 (c1 NCHAR (10), x2 TT_INTEGER);
Command> INSERT INTO convdemo VALUES ('ABC', 10);
1 row inserted.
Command> INSERT INTO convdemo VALUES ('def', 100);
1 row inserted.
Command> INSERT INTO convdemo2 SELECT * FROM convdemo;
2 rows inserted.
Command> SELECT x1,x2,convdemo.c1, convdemo2.c1
> FROM convdemo, convdemo2 where Ccnvdemo.c1 = convdemo2.c1;
X1, X2, C1, C1
< 10, 10, ABC       , ABC        >
< 100, 100, def       , def        >
2 rows found.

Null values

The value

NULL

indicates the absence of a value. It is a placeholder for a value that is missing. Use a

NULL

when the actual value is not known
or when a value would not be meaningful. Do not use

NULL

to represent a numeric value of zero, because they are not equivalent. Any parameter in an expression can contain

NULL

regardless of its data type. In addition, any column in
a table can contain

NULL

, regardless of its data type, unless you specify

NOT NULL

or

PRIMARY KEY

integrity constraints for the column when you create the table.

The following properties of

NULL

affect operations on rows, parameters, or local variables:

By default,

NULL

is sorted as the highest value in a sequence of values.
However, you can modify the sort order value for

NULL

with

NULLS FIRST

or

NULLS LAST

in the

ORDER BY

clause.

Two

NULL

values are not equal to each other except in a

GROUP BY

or

SELECT DISTINCT

operation.

An arithmetic expression containing a

NULL

evaluates to

NULL

. In fact, all operators (except concatenation) return

NULL

when given a

NULL

operand. For example,

(5-col)

, where

col

is

NULL

,
evaluates to

NULL

.

To test for

NULL

, use the comparison conditions

IS NULL

or

IS NOT NULL

. Because

NULL

represents a lack of data, a

NULL

cannot be equal or unequal to any value or to another

NULL

.
Thus, the statement

select * from employees where mgr_id = NULL

evaluates to 0, since you cannot use this comparison to

NULL

. However, the statement

select * from employees where mgr_id is NULL

provides the CEO of the company,
since that is the only employee without a manager. For details, see"IS NULL predicate".

The

NULL

value itself can be used directly as an operand of an operator or predicate. For example, the

(1 = NULL)

comparison is supported. This is the same as if you cast

NULL

to the appropriate data type, as follows:

(1
= CAST(NULL AS INT))

. Both methods are supported and return the same results.

Because of these properties, TimesTen ignores columns, rows, or parameters containing

NULL

when:

Joining tables if the join is on a column containing

NULL

.

Executing aggregate functions.

In several SQL predicates, described in Chapter 5, "Search Conditions," you can explicitly test for

NULL

.
APIs supported by TimesTen offer ways to handle null values. For example, in an ODBC application, use the functions

SQLBindCol

,

SQLBindParameter

,

SQLGetData

,
and

SQLParamData

to handle input and output of

NULL

values.

INF
and NAN

TimesTen supports the IEEE floating-point values

Inf

(positive infinity),

-Inf

(negative infinity), and

NaN

(not a number).

Constant values

You can use constant values in places where a floating-point constant is allowed. The following constants are supported:

BINARY_FLOAT_INFINITY

-BINARY_FLOAT_INFINITY

BINARY_DOUBLE_INFINITY

-BINARY_DOUBLE_INFINITY

BINARY_FLOAT_NAN

BINARY_DOUBLE_NAN

In the following example, a table is created with a column of type

BINARY_FLOAT

and a column of type

TT_INTEGER

.

BINARY_FLOAT_INFINITY

and

BINARY_FLOAT_NAN

are inserted into the column of type

BINARY_FLOAT

.

Command> CREATE TABLE bfdemo (id BINARY_FLOAT, Ii2 TT_INTEGER);
Command> INSERT INTO bfdemo VALUES (BINARY_FLOAT_INFINITY, 50);
1 row inserted.
Command> INSERT INTO bfdemo VALUES (BINARY_FLOAT_NAN, 100);
1 row inserted.
Command> SELECT * FROM bfdemo;
< INF, 50 >
< NAN, 100 >
2 rows found.

Primary key values

Inf

,

-Inf

, and

NaN

are acceptable values in columns defined with a primary key. This is different from

NULL

, which is not allowed in columns defined with a primary key.

You can only insert

Inf

,

-Inf

, and

NaN

values into

BINARY_FLOAT

and

BINARY_DOUBLE

columns.

Selecting Inf and NaN (floating-point conditions)

Floating-point conditions determine whether an expression is infinite or is the undefined result of an operation (

NaN

, meaning not a number).

Consider the following syntax:

<span class="italic">Expression</span> IS [NOT] {NAN|INFINITE}

Expression

must either resolve to a numeric data type or to a data type that can be implicitly converted to a numeric data type.

The following table describes the floating-point conditions.

Condition	Operation	Example
IS [NOT] NAN	Returns TRUE if Expression is the value NaN when NOT is not specified. Returns TRUE if Expression is not the value NaN when NOT is specified.	SELECT * FROM bfdemo WHERE id IS NOT NAN; ID, ID2 < INF, 50 > 1 row found.
IS [NOT] INFINITE	Returns TRUE if Expression is the value +Inf or -Inf when NOT is not specified. Returns TRUE if Expression is neither +Inf nor -Inf when NOT is specified.	SELECT * FROM bfdemo WHERE id IS NOT INFINITE; ID, ID2 < NAN, 100 > 1 row found.

Note:
The constant keywords represent specific

BINARY_FLOAT

and

BINARY_DOUBLE

values. The comparison keywords correspond to properties of a value and are not specific to any type, although they can only evaluate to

TRUE

for

BINARY_FLOAT

or

BINARY_DOUBLE

types
or types that can be converted to

BINARY_FLOAT

or

BINARY_DOUBLE

.
The following rules apply to comparisons with

Inf

and

NaN

:

Comparison between

Inf

(or

-Inf

) and a finite value are as expected. For example, 5 >

-Inf

.

(Inf = Inf)

and

(Inf > -Inf)

both evaluate to

TRUE

.

(NaN = NaN)

evaluates to

TRUE

.

In reference to collating sequences:

-Inf

sorts lower than any other value.

Inf

sorts lower than

NaN

and

NULL

and higher than any other value.

NaN

sorts higher than

Inf

.

NULL

sorts higher than

NaN

.

NULL

is always the largest value in any collating sequence.

Expressions involving Inf and NaN

Expressions containing floating-point values may generate

Inf

,

-Inf

, or

NaN

. This can occur either because the expression generated overflow or exceptional conditions or because one or more of the values in the expression
was

Inf

,

-Inf

, or

NaN

.

Inf

and

NaN

are generated in overflow or division-by-zero conditions.

Inf

,

-Inf

, and

NaN

values are not ignored in aggregate functions.

NULL

values are. If you want to exclude

Inf

and

NaN

from aggregates, or from any

SELECT

result, use
both the

IS NOT NAN

and

IS NOT INFINITE

predicates.

Overflow
and truncation

Some operations can result in data overflow or truncation. Overflow results in an error
and can generate

Inf

. Truncation results in loss of least significant data.

Exact values are truncated only when they are stored in the database by an

INSERT

or

UPDATE

statement,
and if the target column has smaller scale than the value. TimesTen returns a warning when such truncation occurs. If the value does not fit because of overflow, TimesTen returns the special value

Inf

and does not insert the specified value.

TimesTen may truncate approximate values during computations, when values are inserted into the database, or when database values are updated. TimesTen returns an error only upon

INSERT

or

UPDATE

. When overflow with approximate values
occurs, TimesTen returns the special value

Inf

.

There are several circumstances that can cause overflow:

During arithmetic operations, overflow can occur when multiplication results in a number
larger than the maximum value allowed in its type. Arithmetic operations are defined inChapter 3, "Expressions."

When aggregate functions are used, overflow can occur when the sum of several numbers
exceeds the maximum allowable value of the result type. Aggregate functions are defined inChapter 3, "Expressions."

During type conversion, overflow can also occur when, for example, a

TT_INTEGER

value
is converted to a

TT_SMALLINT

value.

Truncation can cause an error or warning for alphanumeric or numeric data types:

For character data, an error occurs if a string is truncated because it is too long
for its target type. For

NCHAR

and

NVARCHAR2

types, truncation always occurs on Unicode character boundaries. In the

NCHAR

data types, a single-byte value (half a Unicode character) has no meaning and is not possible.

For numeric data, a warning occurs when any trailing non-zero digit is dropped from
the fractional part of a numeric value.

Underflow

When an approximate numeric value is too close to zero to be represented by the hardware, TimesTen underflows to zero and returns a truncation warning.

Replication limits

TimesTen places the following limits on the size of data types in a database that is being replicated:

VARCHAR2

and

VARBINARY

columns cannot exceed four megabytes. For character-length semantics, the limit is four megabytes. The database character set determines how many characters can be represented by four megabytes. The minimum
number of characters is 1,000,000/ 4 = 250,000 characters.

NVARCHAR2

columns cannot exceed 500,000 characters (four megabytes).

TimesTen type mode (backward compatibility)

TimesTen supports a data type backward compatibility mode called TimesTen type mode. This is specified using the data store creation attribute

TypeMode

, where

TypeMode=1

indicates TimesTen mode. Type mode determines the default data
type. For example,

DATE

in TimesTen type mode defaults to

TT_DATE

;

DATE

in Oracle type mode defaults to

ORA_DATE

.

For more information on type modes, see "TypeMode" in Oracle
TimesTen In-Memory Database Reference. For information on data type usage in TimesTen type mode, refer toOracle TimesTen In-Memory Database API and SQL Reference Guide, Release 6.0.3.

Data types supported in TimesTen type mode

Table
1-9 Data types supported in TimesTen type mode

Data type	Description
BIGINT	A signed eight-byte integer in the range -9,223,372,036,854,775,808 (-263) to 9,223,372,036,854,775,807 (263-1). Alternatively, specify TT_BIGINT .
BINARY( n )	Fixed-length binary value of n bytes. Legal values for n range from 1 to 8300. BINARY data is padded to the maximum column size with trailing zeroes.
BINARY_DOUBLE	A 64-bit floating-point number. BINARY_DOUBLE is a double-precision native floating point number. Supports +Inf , -Inf , and NaN values. BINARY_DOUBLE is an approximate numeric value consisting of an exponent and mantissa. You can use exponential or E-notation. BINARY_DOUBLE has binary precision 53. Minimum positive finite value: 2.22507485850720E-308 Maximum positive finite value: 1.79769313486231E+308 Alternatively, specify DOUBLE [PRECISION] or FLOAT[(53)] .
BINARY_FLOAT	A 32-bit floating-point number. BINARY_FLOAT is a single-precision native floating-point type. Supports +Inf , -Inf , and NaN values. BINARY_FLOAT is an approximate numeric value consisting of an exponent and mantissa. You can use exponential or E-notation. BINARY_FLOAT has binary precision 24. Minimum positive finite value: 1.17549E-38F Maximum positive finite value: 3.40282E+38F Alternatively, specify REAL or FLOAT(24) .
CHAR[ACTER][( n [BYTE|CHAR])]	Fixed-length character string of length n bytes or characters. Default is one byte. BYTE indicates that the column has byte-length semantics. Legal values for n bytes range from 1 to 8300. CHAR indicates that the column has character-length semantics. The minimum CHAR length is one character. The maximum CHAR length depends on how many characters fit in 8300 bytes. This is determined by the database character set in use. For character set AL32UTF8 , up to four bytes per character may be needed, so the CHAR length limit ranges from 2075 to 8300 depending on the character set. A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. CHAR data is padded to the maximum column size with trailing blanks. Blank-padded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics". Alternatively, specify TT_CHAR[( n [BYTE|CHAR])] .
DATE	Stores date information: century, year, month, and day. The format is YYYY-MM-DD , where MM is expressed as an integer. For example: 2006-10-28. Storage size is four bytes. Valid dates are between 1753-01-01 (January 1,1753) and 9999-12-31 (December 31, 9999). Alternatively, specify TT_DATE .
DEC[IMAL][( p [, s ])] or NUMERIC[( p [, s ])]	An exact numeric value with a fixed maximum precision (total number of digits) and scale (number of digits to the right of the decimal point). The value of precision p must be between 1 and 40. The value of scale s must be between 0 and p . The default precision is 40 and the default scale is 0.
INTERVAL [+/-] IntervalQualifier	TimesTen partially supports interval types, expressed with INTERVAL and an IntervalQualifier . An IntervalQualifier can specify only a single field type with no precision. The default leading precision is eight digits for all interval types. The single field type can be one of: YEAR , MONTH , DAY , HOUR , MINUTE , or SECOND . Currently, interval types can be specified only with a constant.
NCHAR[( n )]	Fixed-length string of n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. NCHAR character limits are half the byte limits, so the maximum size is 4150. Default and minimum bytes of storage is 2 n (2). A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. NCHAR data is padded to the maximum column size with U+0020 SPACE . Blank-padded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics". Alternatively, specify TT_NCHAR[( n )] . NATIONAL CHARACTER and NATIONAL CHAR are synonyms for NCHAR .
SMALLINT	A native signed 16-bit integer in the range -32,768 (-215) to 32,767 (215-1). Alternatively, specify TT_SMALLINT .
TIME	A time of day between 00:00:00 (midnight) and 23:59:59 (11:59:59 pm), inclusive. The format is: HH:MI:SS . Storage size is eight bytes.
TIMESTAMP	A date and time between 1753-01-01 00:00:00 (midnight on January 1, 1753) and 9999-12-31 23:59:59 pm (11:59:59 pm on December 31, 9999), inclusive. Any values for the fraction not specified in full microseconds result in a " Data Truncated " error. The format is YYYY-MM-DD HH:MI:SS [.FFFFFFFFF] . Storage size is eight bytes. Alternatively, specify TT_TIMESTAMP or [TT_]TIMESTAMP(6) .
TINYINT	Unsigned integer ranging from 0 to 255 (28-1). Since TINYINT is unsigned, the negation of a TINYINT is SMALLINT . Alternatively, specify TT_TINYINT .
INT[EGER]	A signed integer in the range -2,147,483,648 (-231) to 2,147,483,647 (231-1). Alternatively, specify TT_INTEGER .
NVARCHAR( n )	Variable-length string of n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. NVARCHAR character limits are half the byte limits so the maximum size is 2,097,152 (221). You must specify n . A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. Blank-padded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics". Alternatively, specify TT_NVARCHAR( n ) . NATIONAL CHARACTER VARYING , NATIONAL CHAR VARYING , and NCHAR VARYING are synonyms for NVARCHAR .
VARCHAR( n [BYTE|CHAR])	Variable-length character string having maximum length n bytes or characters. You must specify n . BYTE indicates that the column has byte-length semantics. Legal values for n bytes range from 1 to 4194304 (222). CHAR indicates that the column has character-length semantics. A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. Blank-padded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics". Alternatively, specify TT_VARCHAR( n [BYTE|CHAR]) .
VARBINARY ( n )	Variable-length binary value having maximum length n bytes. Legal values for n range from 1 to 4194304 (222).

Oracle data types supported in TimesTen type mode

Table
1-10 Oracle data types supported in TimesTen type mode

Data type	Description
NUMBER[( p [, s ])]	Number having precision and scale. The precision value ranges from 1 to 38 decimal. The scale value ranges from -84 to 127. Both precision and scale are optional. If you do not specify a precision or a scale, then maximum precision of 38 and flexible scale are assumed. NUMBER supports scale > precision and negative scale. NUMBER stores zero as well as positive and negative fixed numbers with absolute values from 1.0 x 10-130 up to but not including 1.0 x 10126. If you specify an arithmetic expression whose value has an absolute value greater than or equal to 1.0 x 10126, then TimesTen returns an error. In TimesTen type mode, the NUMBER data type stores 10E-89 as its smallest (closest to zero) value.
ORA_CHAR[( n [BYTE|CHAR])]	Fixed-length character string of length n bytes or characters. Default is one byte. BYTE indicates that the column has byte-length semantics. Legal values for n bytes range from 1 to 8300. CHAR indicates that the column has character-length semantics. The minimum CHAR length is one character. The maximum CHAR length depends on how many characters fit in 8300 bytes. This is determined by the database character set in use. For character set AL32UTF8 , up to four bytes per character may be needed, so the CHAR length limit ranges from 2075 to 8300 depending on the character set. A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. ORA_CHAR data is padded to the maximum column size with trailing blanks. Blank-padded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics".
ORA_DATE	Stores date and time information: century, year, month, date, hour, minute, and second. Format is YYYY-MM-DD HHMMSS . Valid date range is from January 1, 4712 BC to December 31, 9999 AD. The storage size is seven bytes. There are no fractional seconds.
ORA_NCHAR[( n )]	Fixed-length string of length n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. NCHAR character limits are half the byte limits so the maximum size is 4150. Default and minimum bytes of storage is 2 n (2). A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. ORA_NCHAR data is padded to the maximum column size with U+0020 SPACE . Blank-padded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics".
ORA_NVARCHAR2 ( n )	Variable-length string of n two-byte Unicode characters. The number of bytes required is 2* n where n is the specified number of characters. ORA_NVARCHAR2 character limits are half the byte limits so the maximum size is 2,097,152 (221). You must specify n . A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. Nonpadded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics".
ORA_VARCHAR2( n [BYTE|CHAR])	Variable-length character string having maximum length n bytes or characters. BYTE indicates that the column has byte-length semantics. Legal values for n bytes range from 1 to 4194304 (222). You must specify n . CHAR indicates that the column has character-length semantics. A zero-length string is a valid non-NULL value. The string value "" is an empty, zero-length string, but not a NULL value. However, in PL/SQL, a zero-length string is always considered to be NULL . Therefore, when you use PL/SQL, any empty string parameter in SQL is converted to NULL by PL/SQL before the value is passed to the TimesTen database. Nonpadded comparison semantics are used. For information on blank-padded and nonpadded semantics, see"Blank-padded and nonpadded comparison semantics".
ORA_TIMESTAMP [( fractional_seconds_precision )]	Stores year, month, and day values of the date data type plus hour, minute, and second values of time. Fractional_seconds_precision is the number of digits in the fractional part of the seconds field. Valid date range is from January 1, 4712 BC to December 31, 9999 AD. The fractional seconds precision range is 0 to 9. The default is 6. Format is: YYYY-MM-DD HH:MI:SS [.FFFFFFFFF] Storage size is 12 bytes.

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