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
- TableName
TruncateTableStmt ::=
"TRUNCATE" ( "TABLE" )? TableName
TableName ::=
(Identifier ".")? Identifier
示例
CREATE TABLE t1 (a INT NOT NULL PRIMARY KEY);
Query OK, 0 rows affected (0.11 sec)
INSERT INTO t1 VALUES (1),(2),(3),(4),(5);
Query OK, 5 rows affected (0.01 sec)
Records: 5 Duplicates: 0 Warnings: 0
SELECT * FROM t1;
+---+
| a |
+---+
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
+---+
5 rows in set (0.00 sec)
TRUNCATE t1;
Query OK, 0 rows affected (0.11 sec)
SELECT * FROM t1;
Empty set (0.00 sec)
INSERT INTO t1 VALUES (1),(2),(3),(4),(5);
Query OK, 5 rows affected (0.01 sec)
Records: 5 Duplicates: 0 Warnings: 0
TRUNCATE TABLE t1;
Query OK, 0 rows affected (0.11 sec)
MySQL 兼容性
TRUNCATE 语句与 MySQL 完全兼容。如发现任何兼容性差异，请尝试 TiDB 支持资源。