// TRUNCATE// 默认规范配置// innodb_flush_method = on & innodb_flush_method = O_DIRECT(root@127.1)[eolbimsdb]08:44:4615>truncate table t5;QueryOK,0rowsaffected(0.98sec)// 设置 innodb_adaptive_hash_index = off(root@127.1
例1 新建表 tb_student_course,插入数据并查询,SQL 语句和运行结果如下: mysql>CREATE TABLE `tb_student_course` (-> `id`int(4) NOT NULL AUTO_INCREMENT,-> `name` varchar(25) NOT NULL,->PRIMARY KEY (`id`)->); Query OK,0rows affected (0.04sec) mysql> INSERT INTO tb_student_course(na...
耗时的过程在que_eval_sql: query: PROCEDURE DROP_TABLE_PROC ---> dict_drop_index_tree; row_drop_single_table_tablespace的耗时被 MySQL 5.7 配置innodb_flush_method=O_DIRECT优化了。 Q2:该优化是否适用于 MySQL 8.0? 设置innodb_flush_method=O_DIRECT的优化操作,同样适用于 MySQL 8.0。 Q3:MySQL 8.0...
适用于:Microsoft Fabric Microsoft Fabric SQL 数据库中的 SQL Server Azure SQL 数据库 Azure SQL 托管实例 Azure Synapse Analytics Analytics Platform System (PDW) Warehouse 删除表中的所有行或表中指定的分区,不记录单个行删除操作。 TRUNCATE TABLE与没有DELETE子句的WHERE语句类似;但是,速度更快,TRUNCATE ...
Query OK, 0 rows affected (0.03 sec) // 设置 innodb_flush_method = fsync (root@127.1) [eolbimsdb] 09:03:34 28> truncate table t5; Query OK, 0 rows affected (1.04 sec) // 设置 innodb_adaptive_hash_index = off & innodb_flush_method = fsync ...
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...
obclient [OBORACLE]> alter table OBORACLE.F2 disable constraint FK_ID; Query OK, 0 rows affected (0.056 sec) 再次truncate 表操作。 obclient [OBORACLE]> truncate table f1; ORA-00600: internal error code, arguments: -5594, Cannot truncate a table referenced in a foreign key constraint (`...
Next, we can verify this with this SQL query: SELECT * FROM Department; We can see the output of the executed SQL query: As seen above, all the records were deleted and the table still exists. 3. What Is aDELETEStatement In contrast to theTRUNCATEstatement,theDELETEstatement in SQL is ...
新建表 tb_student_course,插入数据并查询,SQL 语句和运行结果如下: mysql> CREATE TABLE `tb_student_course` ( -> `id` int(4) NOT NULL AUTO_INCREMENT, -> `name` varchar(25) NOT NULL, -> PRIMARY KEY (`id`) -> ); Query OK, 0 rows affected (0.04 sec) ...
Query OK, 0 rows affected (0.03 sec) // 设置 innodb_flush_method = fsync (root@127.1) [eolbimsdb] 09:03:34 28> truncate table t5; Query OK, 0 rows affected (1.04 sec) // 设置 innodb_adaptive_hash_index = off & innodb_flush_method = fsync ...