文档课题：验证oracle创建唯一键后索引的自动生成.
数据库：oracle 11.2.0.4
1、原表数据
HR@orcl150> DESC test2;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 ID                                                 NUMBER(4)
 NAME                                               VARCHAR2(20)
HR@orcl150> select * from test2;

        ID NAME
---------- --------------------
         1 henrry
2、添加约束
HR@orcl150> alter table test2 add constraint indx_test2_id unique (id) enable novalidate;

Table altered.
3、数据验证
HR@orcl150> col owner for a10
HR@orcl150> col CONSTRAINT_NAME for a20
HR@orcl150> col TABLE_NAME for a15
HR@orcl150> set line 200
HR@orcl150> select owner,constraint_name,constraint_type,table_name from user_constraints where table_name='TEST2';

OWNER      CONSTRAINT_NAME      C TABLE_NAME
---------- -------------------- - ---------------
HR         INDX_TEST2_ID        U TEST2

HR@orcl150> select INDEX_NAME from user_indexes where table_name='TEST2';

INDEX_NAME
------------------------------
INDX_TEST2_ID

结论：表添加唯一键后，会自动生成相应索引.