Home Database Mysql Tutorial Access数据库多表连接查询

Access数据库多表连接查询

Jun 07, 2016 pm 03:44 PM
access database Inquire connect

第一次在Access中写多表查询,就按照MS数据库中的写法,结果报语法错,原来Access的多表连接查询是不一样的 表A、B、C,A关联B,B关联C,均用ID键关联 一般写法:select * from A inner join B on A.ID=B.ID inner join C on B.ID=C.ID 此写法在Access中报错

第一次在Access中写多表查询,就按照MS数据库中的写法,结果报语法错,原来Access的多表连接查询是不一样的

表A、B、C,A关联B,B关联C,均用ID键关联

一般写法:select * from A inner join B on A.ID=B.ID inner join C on B.ID=C.ID

此写法在Access中报错,Access对SQL语法理解方式不一样,它将两表连接后当作一个表然后再与第三个表连接,因此要改成

select * from (A inner join B on A.ID=B.ID ) inner join C on B.ID=C.ID

若出现第4张表D呢?

select * from ((A inner join B on A.ID=B.ID ) inner join C on B.ID=C.ID)  inner join D on C.ID=D.ID

……

可以理解为始终是两表间的操作

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