mysql查询索引的方法 ：
比如想查emp的索引：
可以使用以下语句：
show index from emp;
也可以通过sql语句来查
select tab.name as "table_name",idx.name as "index_name",
fld.name as "index_column_name",fld.pos as "index_column_pos"
from
information_schema.innodb_sys_indexes idx,
information_schema.innodb_sys_tables tab,
information_schema.INNODB_SYS_FIELDS fld
where idx.table_id=tab.table_id
and idx.index_id=fld.index_id
and tab.name like 'sztech/emp'
mysql> show index from sztech.emp;
+-------+------------+---------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-------+------------+---------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| emp | 1 | idx_emp_empid | 1 | empid | A | 2 | NULL | NULL | | BTREE | | |
+-------+------------+---------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
1 row in set (0.00 sec)
mysql> select tab.name as "table_name",idx.name as "index_name",
-> fld.name as "index_column_name",fld.pos as "index_column_pos"
-> from
-> information_schema.innodb_sys_indexes idx,
-> information_schema.innodb_sys_tables tab,
-> information_schema.INNODB_SYS_FIELDS fld
-> where idx.table_id=tab.table_id
-> and idx.index_id=fld.index_id
-> and tab.name like 'sztech/emp'
-> ;
+------------+---------------+-------------------+------------------+
| table_name | index_name | index_column_name | index_column_pos |
+------------+---------------+-------------------+------------------+
| sztech/emp | idx_emp_empid | empid | 0 |
+------------+---------------+-------------------+------------------+
1 row in set (0.00 sec)
| 欢迎光临 重庆思庄Oracle、Redhat认证学习论坛 (http://bbs.cqsztech.com/) | Powered by Discuz! X3.2 |