oracle 删除数据
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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