Oracle 使用TRANSLATE函数替换字符串中的字符

一个需求，如何将(1234,56789,12345)替换为'1234*56789*12345'?

第一种方式,使用replace:

ChenZw> SELECT REPLACE(REPLACE(REPLACE('(1234,56789,12345)',',','*'),'(',''''),')','''') FROM DUAL;

REPLACE(REPLACE(RE
------------------
'1234*56789*12345'

已选择 1 行。

上面的代码明显比较粗鲁,下面看一下Replace函数的官方介绍:

Purpose

REPLACE

returns

char

with every occurrence of

search_string

replaced
with

replacement_string

. If

replacement_string

is omitted
or null, then all occurrences of

search_string

are removed. If

search_string

is
null, then

char

is returned.

Both

search_string

and

replacement_string

, as well as

char

,
can be any of the data types

CHAR

,

VARCHAR2

,

NCHAR

,

NVARCHAR2

,

CLOB

, or

NCLOB

.
The string returned is in the same character set as

char

. The function returns

VARCHAR2

if the first argument is not a LOB
and returns

CLOB

if the first argument is a LOB.

Examples
The following example replaces occurrences of

J

with

BL

:

SELECT REPLACE('JACK and JUE','J','BL') "Changes"
     FROM DUAL;

Changes
--------------
BLACK and BLUE

第二种方式,使用translate函数:

ChenZw> SELECT TRANSLATE('(1234,56789,12345)','(,)','''*''') AS STR FROM DUAL;
STR
------------------
'1234*56789*12345'
已选择 1 行。
使用这个函数处理这个问题就看起来比较舒服一点,至少没有replace那么暴力,看一下官方关于translate函数的介绍:

Purpose

TRANSLATE

returns

expr

with all occurrences of each character in

from_string

replaced
by its corresponding character in

to_string

. Characters in

expr

that
are not in

from_string

are not replaced. The argument

from_string

can
contain more characters than

to_string

. In this case, the extra characters at the end of

from_string

have
no corresponding characters in

to_string

. If these extra characters appear in

expr

,
then they are removed from the return value.

If a character appears multiple times in

from_string

, then the

to_string

mapping
corresponding to the first occurrence is used.

You cannot use an empty string for

to_string

to remove all characters in

from_string

from
the return value. Oracle Database interprets the empty string as null, and if this function has a null argument, then it returns null. To remove all characters in

from_string

,
concatenate another character to the beginning of

from_string

and specify this character as the

to_string

.
For example,

TRANSLATE

(

expr

, '

x0123456789

', '

x

')
removes all digits from

expr

.

TRANSLATE

provides functionality related to that provided by the

REPLACE

function.

REPLACE

lets you substitute a single string for another single string,
as well as remove character strings.

TRANSLATE

lets you make several single-character, one-to-one substitutions in one operation.

This function does not support

CLOB

data directly. However,

CLOB

s can be passed in as arguments through implicit data conversion.

Examples

The following statement translates a book title into a string that could be used (for example) as a filename. The

from_string

contains four characters: a space,
asterisk, slash, and apostrophe (with an extra apostrophe as the escape character). The

to_string

contains only three underscores. This leaves the fourth character
in the

from_string

without a corresponding replacement, so apostrophes are dropped from the returned value.

SELECT TRANSLATE('SQL*Plus User''s Guide', ' */''', '___') FROM DUAL;

TRANSLATE('SQL*PLUSU
--------------------
SQL_Plus_Users_Guide

作者 陈字文（热衷于PM\ORACLE\J***A等，欢迎同行交流):ziwen#163.com 扣扣:4零9零2零1零零