delete是DML语句,这个操作会被放到 rollback segment中,事务提交后才生效。如果有相应的触发器,执行的时候将被触发。 2、语法结构不同,truncate会删除表中所有数据,delete后面可以跟where进行条件过滤,如果不跟任何条件,也会删除所有数据... jmeter访问数据库-JDBC Request(mysql/mssql/oracle/postgresql)...
In this example, theemployeestable is a partitioned table and the TRUNCATE TABLE statement would truncate partitions 1 through 5 as well as partition 7 in this partitioned table. Frequently Asked Questions Question:Can you rollback a TRUNCATE TABLE statement in SQL Server? Answer:A TRUNCATE TABLE...
一、相同点: 都会删除数据表中的数据 二、异同点: 所属的SQL语言类别、删除数据表的效果、操作的效率、安全风险不一样 SQL语言类别 delete为数据库操作语言(DML),操作后原数据会放到rollback segement中,可回滚 truncate/drop为数据库定义语言(DDL),操作后原数据不会放到rollback segment中,不能回滚 数据表的删除...
Great back to basics question. We have seen this topic on QOTD many times. Still quite shocking that at the time of my comment there are 33% of the answers thinking that TRUNCATE will not be rolled back. I agree that's shocking, but I'm even more shocked that 8% of answers believe ...
Truncate the table within a transaction, and check the number of rows. SQL კოპირება BEGIN TRANSACTION; TRUNCATE TABLE TruncateTest; SELECT ID FROM TruncateTest; You see that the table is empty. Roll back the transaction and check the data. SQL კოპირე...
mysq1> rollback; //回滚 Query OK,0 rows affected (0.00 sec) mysql> select * from user_bak; //查询也没有内容 Empty set (0.00 sec) mysql> 这就是 delete 操作可以回滚,truncate 操作不能回滚。文章标签: 云数据库 RDS MySQL 版 Shell SQL 关系型数据库 MySQL 安全 数据库 开发者 关键词: ...
删除表中的所有数据,不能与where一起使用 3、delete from tb (where) 删除表中的数据(可制定某一行) -...--- 区别:truncate和delete的区别 1、事务:truncate是不可以rollback的,但是delete是可以rollback的;...原因:truncate删除整表数据(ddl语句,隐式提交),delete是一行一行的删除,可以rollback 2、效果:...
Further, we’ll explore the practical usage of the TRUNCATE TABLE statement in SQL and delete thePersonstable data from theAdventureWorks2019database. First, let’s see how many rows the table contains. To do this, we’ll execute the SELECT query with the COUNT(*) function that returns the...
Rollback is possible. DELETE and TRUNCATE both can be rolled back when used with TRANSACTION (TRUNCATE can be rolled back in SQL Server, but not in MySQL). if there is a PK with auto increment, truncate will reset the counter http://beginner-sql-tutorial.com/sql-delete-statement.htm...
truncate,drop是ddl, 操作立即生效,原数据不放到rollback segment中,不能回滚. 操作不触发trigger. 3.delete语句不影响表所占用的extent, 高水线(high watermark)保持原位置不动 显然drop语句将表所占用的空间全部释放 truncate 语句缺省情况下见空间释放到 minextents个 extent,除非使用reuse storage; truncate会将高...