8.Oracle杂记——数据字典dba_ind_columns

8.Oracle杂记——数据字典dba_ind_columns
视图dba_ind_columns表示在所有表及聚集上索引的列。

视图如下：

sys@PDB1> desc dba_ind_columns

 Name                                                                                                     Null?         Type

 ------------------------------------------------------------- ------------------------------------

 INDEX_OWNER                                                                                  NOT NULL VARCHAR2(128)

 INDEX_NAME                                                                                     NOT NULL VARCHAR2(128)

 TABLE_OWNER                                                                                  NOT NULL VARCHAR2(128)

 TABLE_NAME                                                                                     NOT NULL VARCHAR2(128)

 COLUMN_NAME                                                                                                                              VARCHAR2(4000)

 COLUMN_POSITION                                                                       NOT NULL NUMBER

 COLUMN_LENGTH                                                                                              NOT NULL NUMBER

 CHAR_LENGTH                                                                                                                NUMBER

 DESCEND                                                                                                                           VARCHAR2(4)

                  列中说明如下：

INDEX_OWNER：索引的拥有者

 INDEX_NAME：索引的名字

 TABLE_OWNER：表或簇的拥有者

 TABLE_NAME：表的名字

 COLUMN_NAME：列名字

 COLUMN_POSITION：索引中列的位置

 COLUMN_LENGTH：列的索引长度

 CHAR_LENGTH：列中最大代码点长度

 DESCEND：列是否按降序排列

执行如下：

Col index_owner format a15

Col index_name format a15

Col table_owner format a15

Col table_name format a15

Col column_name format a15

Set linesize 1000

sys@PDB1> select * from dba_ind_columns whererownum <= 1;

 

INDEX_OWNER     INDEX_NAME        TABLE_OWNER     TABLE_NAME        COLUMN_NAME  COLUMN_POSITION COLUMN_LENGTH CHAR_LENGTH DESC

--------------- ------------------------------ --------------- --------------- --------------- ------------------------ ----

SYS                             I_PARAMETER1    SYS                             PARAMETER$        NAME                                               4                   128            128 ASC