基于封技术、基于时戳技术、基于有效性检查、MVCC 等技术是并发控制技术
mysql> create table z (
-> a int not null,
-> b int null...unique key (b),
-> unique key (d),
-> unique key (c));
Query OK, 0 rows affected (0.09 sec)
mysql...into z select 1,2,3,4;
Query OK, 1 row affected (0.01 sec)
Records: 1 Duplicates: 0 Warnings: 0
mysql...into z select 5,6,7,8;
Query OK, 1 row affected (0.01 sec)
Records: 1 Duplicates: 0 Warnings: 0
mysql...into z select 9,10,11,12;
Query OK, 1 row affected (0.01 sec)
Records: 1 Duplicates: 0 Warnings: 0
mysql