请问SQL五个表联合查询问题

如下,每个表的字段都是相同的
select ywrq,hhywlb,JGDM,GLBDM,JBYHDM,count(*) from zjhhyw.jy_jcywb group by ywrq,hhywlb,JGDM,GLBDM,JBYHDM order by ywrq
union all
select ywrq,hhywlb,JGDM,GLBDM,JBYHDM,count(*) from zjhhyw.jy_tqywb group by ywrq,hhywlb,JGDM,GLBDM,JBYHDM order by ywrq
union all
select ywrq,hhywlb,JGDM,GLBDM,JBYHDM,count(*) from zjhhyw.jy_dbhsywb group by ywrq,hhywlb,JGDM,GLBDM,JBYHDM order by ywrq
union all
select ywrq,hhywlb,JGDM,GLBDM,JBYHDM,count(*) from zjhhyw.jy_dbtqywb group by ywrq,hhywlb,JGDM,GLBDM,JBYHDM order by ywrq
union all
select ywrq,hhywlb,JGDM,GLBDM,JBYHDM,count(*) from zjhhyw.jy_zhhbywb group by ywrq,hhywlb,JGDM,GLBDM,JBYHDM order by ywrq

每个单句都是通的 但是加上union all就不通了,我用的是as400数据库

上面那个问题终于解决了 接着是

select * from ( select ywrq,hhywlb,JGDM,GLBDM,JBYHDM,count(*) from zjhhyw.jy_tqywb group by ywrq,hhywlb,JGDM,GLBDM,JBYHDM )
里面有个字段JGDM不在表里,而在另一个zjhhyw.jy_tqywmxb里,这个如何合并

你把每个字段都加上转换 函数转换成指定类型再合并，在结构上不是同一个表的结构，所以数据库是不认的。

select py form py where p_id in (select py from zi where zi='鲤');