只能通过ALTER TABLE不能create index
ALTER TABLE tbl_name ADD PRIMARY KEY (column), ALGORITHM=INPLACE, LOCK=NONE;
参数说明：
ALGORITHM=INPLACE
更优秀的解决方案，在当前表加索引，步骤：
1.创建索引(二级索引)数据字典
2.加共享表锁，禁止DML，允许查询
3.读取聚簇索引，构造新的索引项，排序并插
入新索引
4.等待打开当前表的所有只读事务提交
5.创建索引结束
ALGORITHM=COPY
通过临时表创建索引，需要多一倍存储，还有更多的IO，步骤：
1.新建带索引（主键索引）的临时表
2.锁原表，禁止DML，允许查询
3.将原表数据拷贝到临时表
4.禁止读写,进行rename，升级字典锁
5.完成创建索引操作
LOCK=DEFAULT：默认方式，MySQL自行判断使用哪种LOCK模式，尽量不锁表
LOCK=NONE：无锁：允许Online DDL期间进行并发读写操作。如果Online DDL操
作不支持对表的继续写入，则DDL操作失败，对表修改无效
LOCK=SHARED：共享锁：Online DDL操作期间堵塞写入，不影响读取
LOCK=EXCLUSIVE：排它锁：Online DDL操作期间不允许对锁表进行任何操作
给1E数据库在线加索引
数据库在线加索引
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Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MySQL [(none)]> use sdorica_exp
MySQL [sdorica_exp]> show index from gashapon_outcome_records;
Empty set (0.00 sec)
MySQL [sdorica_exp]> select count(1) from gashapon_outcome_records;
+-----------+
| count(1) |
+-----------+
| 111579926 |
+-----------+
1 row in set (1 min 10.13 sec)
MySQL [sdorica_exp]> ALTER TABLE gashapon_outcome_records ADD INDEX idx_roll_gashapon_record_id (roll_gashapon_record_id) , ALGORITHM=INPLACE, LOCK=NONE;
Query OK, 0 rows affected (15 min 34.16 sec)
Records: 0 Duplicates: 0 Warnings: 0
MySQL [sdorica_exp]> show index from gashapon_outcome_records;
+--------------------------+------------+-----------------------------+--------------+-------------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+--------------------------+------------+-----------------------------+--------------+-------------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| gashapon_outcome_records | 1 | idx_roll_gashapon_record_id | 1 | roll_gashapon_record_id | A | 51825872 | NULL | NULL | YES | BTREE | | |
+--------------------------+------------+-----------------------------+--------------+-------------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
1 row in set (0.01 sec)
MySQL [sdorica_exp]>