TRUNCATE
TRUNCATE
语句以非事务方式从表中删除所有数据。可认为 TRUNCATE
语句同 DROP TABLE
+ CREATE TABLE
组合在语义上相同,定义与 DROP TABLE
语句相同。
TRUNCATE TABLE tableName
和 TRUNCATE tableName
均为有效语法。
语法图
TruncateTableStmt:
OptTable:
TableName:
示例
mysql> CREATE TABLE t1 (a INT NOT NULL PRIMARY KEY);
Query OK, 0 rows affected (0.11 sec)
mysql> INSERT INTO t1 VALUES (1),(2),(3),(4),(5);
Query OK, 5 rows affected (0.01 sec)
Records: 5 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM t1;
+---+
| a |
+---+
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
+---+
5 rows in set (0.00 sec)
mysql> TRUNCATE t1;
Query OK, 0 rows affected (0.11 sec)
mysql> SELECT * FROM t1;
Empty set (0.00 sec)
mysql> INSERT INTO t1 VALUES (1),(2),(3),(4),(5);
Query OK, 5 rows affected (0.01 sec)
Records: 5 Duplicates: 0 Warnings: 0
mysql> TRUNCATE TABLE t1;
Query OK, 0 rows affected (0.11 sec)
MySQL 兼容性
TRUNCATE
语句与 MySQL 完全兼容。如有任何兼容性差异,请在 GitHub 上提交 issue。