Access数据库多表连接查询
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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