mysql> show create table table_test;
+---------------------------------------+---------------------------+
| Table | Create Table |
+---------------------------------------+---------------------------+
| table_test | CREATE TABLE `table_test` (
`id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '涓婚敭',

`activity_id` varchar(20) NOT NULL COMMENT '媧誨姩ID',
`store_code` varchar(100) NOT NULL COMMENT '媧誨姩鍚嶇О',
`generation_date` date DEFAULT NULL COMMENT '鐢熸垚鏃ユ湡,鏍煎紡錛歽yyy-MM-dd',
`ordercon_num` bigint(20) DEFAULT '0' COMMENT '璁㈠崟杞寲浜烘暟',
`create_time` datetime DEFAULT CURRENT_TIMESTAMP COMMENT '鍒涘緩鏃墮棿',
`update_time` datetime DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP COMMENT '鏇存柊鏃墮棿',
`delete_flag` varchar(1) DEFAULT '1' COMMENT '鐘舵€?1-鍚敤錛?-鍒犻櫎',
PRIMARY KEY (`id`),
UNIQUE KEY `uk_activityid_date` (`activity_id`,`generation_date`) USING BTREE,
KEY `idx_storecode` (`store_code`) USING BTREE
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='搴楅摵緇村害澶╄〃' |
+---------------------------------------+---------------------------
亂碼正好算加密了~

刪除聯合主鍵索引：

ALTER TABLE table_test DROP INDEX `uk_activityid_date`;

新增索引：

ALTER TABLE table_test ADD INDEX `idx_activityid` (`activity_id`) USING BTREE;