insert DELETEUPDATE语句.ppt
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数据操纵语言 5.4.2 UPDATE语句 (p98) UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] UPDATE语句的基本格式: UPDATE table_name SET column_name=expression [FROM table_source] [WHERE search_conditions] 5.4.3 DELETE语句 (p98) DELETE语句的基本格式: DELETE [FROM] table_name [WHERE search_conditions] DELETE语句的基本格式: DELETE [FROM] table_name [WHERE search_conditions] DELETE语句的基本格式: DELETE [FROM] table_name [WHERE search_conditions] DELETE语句的基本格式: DELETE [FROM] table_name [WHERE search_conditions] DELETE语句的基本格式: DELETE [FROM] table_name [WHERE search_conditions] DELETE语句的基本格式: DELETE [FROM] table_name [WHERE search_conditions] TRUNCATE TABLE语句 TRUNCATE TABLE语句的基本格式: TRUNCATE TABLE table_name 例如,如下语句将删除表tb_booktemp中的所有行: TRUNCATE TABLE tb_booktemp 在执行结果上等价于如下语句: DELETE FROM tb_booktemp 但在运行速度上,使用TRUNCATE TABLE语句要快一些,因为该语句一次删除所有行,而DELETE语句是每次删除一行。 * (续) Transact-SQL语言 SQL语言中的语言可以从功能上分为3类: 数据定义语言 DDL 数据处理语言 DML 数据控制语言 DCL 数据处理语言(Data Manipulation Language,简写DML)是指用来
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