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HomeDatabaseMysql Tutorial Access入门教程17.2基本的SQL语句[1]

Access入门教程17.2基本的SQL语句[1]

Jun 07, 2016 pm 04:02 PM
accesssqlGetting Started TutorialBasicstatement

在SQL语言中用得最多的就是SELECT语句了 我们就先讲讲SELECT语句吧 SELECT语句构成了SQL数据库语言的核心 它的语法包括 个主要子句 分别是FORM WHERE GROUP BY HAVING ORDER BY子句 SELECT语句的结构是这样的 SELECT 〈字段列表〉 FROM 〈表列表〉 [ WHERE〈

    在SQL语言中用得最多的就是SELECT语句了我们就先讲讲SELECT语句吧    SELECT语句构成了SQL数据库语言的核心它的语法包括个主要子句分别是FORMWHEREGROUP BYHAVINGORDER BY子句

    SELECT语句的结构是这样的 SELECT 〈字段列表〉 FROM 〈表列表〉 [ WHERE〈行选择说明〉][GROUP BY 〈分组说明〉][ HAVING 〈组选择说明〉] [ORDER BY 〈排序说明〉];


Access入门教程17.2基本的SQL语句[1]

    实际上当我们要将表的字段和字段用来建立一个查询的话只需要书写下面这样一条语句就可以了 SELECT 表字段字段(表的名字字段名最好和具体的例子结合起来下同) FROM 表;

    我们可以这样理解这句话从表中选择出字段和字段选中的每个字段都用逗号隔开并且每个字段前面都列的有表或查询的名字并用联起来而FROM后面则需要有包含这些字段的所有表的名称各个名称之间要用逗号联接起来


Access入门教程17.2基本的SQL语句[1]

    现在我们可以单击工具菜单上的执行按钮
Access入门教程17.2基本的SQL语句[1]


Access入门教程17.2基本的SQL语句[1]

    现在我们看到了这个查询的结果和直接用查询视图设计的查询产生了相同的效果其实ACCESS中所有的数据库操作都是由SQL语言构成的微软公司只是在其上增加了更加方便的操作向导和可视化设计罢了

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