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oracle 删除数据Jun 07, 2016 pm 03:07 PM
oracledeletedatain the table

Oracle在表中删除数据的语法是: 语法结构: DELETE FROM表名 WHERE 条件 代码演示: SQL DELETE FROM INFOS WHERE STUID=s100103; 1 ROW DELETED SQL COMMIT; TRUNCATE 在数据库操作中, TRUNCATE命令(是一个DDL命令)可以把表中的所有数据一次性全部删除

Oracle在表中删除数据的语法是:

语法结构:

DELETE FROM表名 WHERE 条件


代码演示:

SQL> DELETE FROM INFOS WHERE STUID='s100103'; 
1 ROW DELETED 
SQL> COMMIT;


TRUNCATE

在数据库操作中, TRUNCATE命令(是一个DDL命令)可以把表中的所有数据一次性全部删除,语法是:

语法结构:

TRUNCATE TABLE 表名


TRUNCATE和DELETE都能把表中的数据全部删除,他们的区别是:
1、TRUNCATE是DDL命令,删除的数据不能恢复;DELETE命令是DML命令,删除后的数据可以通过日志文件恢复。
2、如果一个表中数据记录很多,TRUNCATE相对DELETE速度快。

由于TRUNCATE命令比较危险,因此在实际开发中,TRUNCATE命令慎用。

 

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