describe etc_category_metadata;
+---------------------+---------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+---------------------+---------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| user_id | bigint(20) | NO | | NULL | |
| time_updated | int(11) | YES | | NULL | |
| category_type | int(11) | YES | MUL | NULL | |
| status_keywords | mediumblob | YES | | NULL | |
| page_keywords | mediumblob | YES | | NULL | |
| profession_keywords | mediumblob | YES | | NULL | |
| adgroup_ids | mediumblob | YES | | NULL | |
| prod | tinyint(1) | YES | | 0 | |
| version | int(11) | YES | | 1 | |
| status | int(11) | YES | | 0 | |
| dep_category_ids | mediumblob | YES | | NULL | |
| custom_param | mediumblob | YES | | NULL | |
| queue_priority | int(11) | YES | | 1 | |
| auto_requeue_num | int(11) | YES | | 0 | |
| cloned_version | int(11) | YES | | 0 | |
| custom_query | varchar(1000) | YES | | NULL | |
| description | varchar(1000) | YES | | NULL | |
| error_message | mediumblob | YES | | NULL | |
| time_last_completed | int(11) | YES | | NULL | |
+---------------------+---------------+------+-----+---------+----------------+
21 rows in set (0.40 sec)
show index from etc_category_metadata;
+-----------------------+------------+-----------------+--------------+---------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-----------------------+------------+-----------------+--------------+---------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| etc_category_metadata | 0 | PRIMARY | 1 | id | A | 12613 | NULL | NULL | | BTREE | | |
| etc_category_metadata | 0 | category_type | 1 | category_type | A | 12613 | NULL | NULL | YES | BTREE | | |
| etc_category_metadata | 0 | category_type | 2 | version | A | 12613 | NULL | NULL | YES | BTREE | | |
| etc_category_metadata | 0 | category_type_2 | 1 | category_type | A | 12613 | NULL | NULL | YES | BTREE | | |
| etc_category_metadata | 0 | category_type_2 | 2 | version | A | 12613 | NULL | NULL | YES | BTREE | | |
| etc_category_metadata | 0 | category_type_3 | 1 | category_type | A | 12613 | NULL | NULL | YES | BTREE | | |
| etc_category_metadata | 0 | category_type_3 | 2 | version | A | 12613 | NULL | NULL | YES | BTREE | | |
+-----------------------+------------+-----------------+--------------+---------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
7 rows in set (0.07 sec)
试图弄清楚是否安全删除键category_type_2
和category_type_3
。看起来它们是与category_type
完全相同的索引。这是一个我不知道谁在很长时间前创建的遗留表。有任何有效原因会导致人们创建这三个看起来是重复的密钥吗?