1、显示当前用户索引信息(DBA_INDEXES,ALL_INDEXES,USER_INDEXES)
03:41:37 SQL> select index_name,index_type,uniqueness
03:41:49   2   from user_indexes;
INDEX_NAME      INDEX_TYPE      UNIQUENES
--------------- --------------- ---------
PK_EMP          NORMAL          UNIQUE
PK_DEPT         NORMAL          UNIQUE
R_EMPNO_IND     NORMAL/REV      NONUNIQUE
EMPNO_INDX      NORMAL          NONUNIQUE
INDX_ENAME      FUNCTION-BASED  NONUNIQUE
NORMAL
PK_SALE         IOT - TOP       UNIQUE
PK_DEPTNO       NORMAL          NONUNIQUE
7 rows selected.
2、显示索引列
03:44:27 SQL> col column_name for a15
03:44:43 SQL> r
1  select column_name,column_position,column_length
2* from user_ind_columns
COLUMN_NAME     COLUMN_POSITION COLUMN_LENGTH
--------------- --------------- -------------
DEPTNO                        1            22
ID                            1            22
EMPNO                         1            22
ENAME                         1            10
SYS_NC00008$                  1            10
DEPTNO                        1            22
EMPNO                         1            22
ENAME                         1            10
8 rows selected.
3、显示索引段的位置和尺寸
03:46:13 SQL> select tablespace_name,segment_type,bytes
03:46:22   2   from user_segments;
TABLESPACE_NAME SEGMENT_TYPE         BYTES
--------------- --------------- ----------
USERS           INDEX                65536
USERS           INDEX                65536
USERS           INDEX                65536
USERS           TABLE                65536
USERS           TABLE                65536
USERS           INDEX                65536
USERS           TABLE                65536
USERS           CLUSTER              65536
USERS           TABLE                65536
USERS           TABLE                65536
USERS           TABLE                65536
USERS           INDEX                65536
USERS           TABLE                65536
USERS           INDEX                65536
USERS           TABLE                65536
USERS01         INDEX               131072
USERS01         TABLE               131072
TABLESPACE_NAME SEGMENT_TYPE         BYTES
--------------- --------------- ----------
USERS02         TABLE                65536
18 rows selected.
4、显示函数索引
03:47:39 SQL> select column_expression from user_ind_expressions;
COLUMN_EXPRESSION
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LOWER("ENAME")