摘要:
有时候,我们需要得到全连接的效果,如下例:create table t1 (id1 int, name1 varchar(20))create table t2 (id2 int, name2 varchar(20))insert into t1 values(1,'a')insert into t1 values(2,'b')insert into t2 values(1,'c')insert into t2 values(3,'d')我们想得到如下结果:1 a c 2 b3 d对于这种需求,理所当然地想到全连接FULL JOI 阅读全文