table1 :code name
c1 n1
c2 n2table2 :code name
c1 n1
c3 n3select code , name from table1
union
select code , name from table1 returns:code name
c1 n1
c2 n2
c3 n3
c1 n1
c2 n2table2 :code name
c1 n1
c3 n3select code , name from table1
union
select code , name from table1 returns:code name
c1 n1
c2 n2
c3 n3
解决方案 »
免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货