SELECT a.id,a.title,a.addtime from table1 union SELECT id,title,addtime from table2 union SELECT id,title,addtime from table3 order by a.addtime
union all吧 union会把内容相同的过滤掉
SELECT id,title,addtime from table1 union all SELECT id,title,addtime from table2 union SELECT id,title,addtime from table3 order by addtime
SELECT id,title,addtime from table1 union all SELECT id,title,addtime from table2 union all SELECT id,title,addtime from table3 order by addtime
union all 或者如果有关联的花就用联合查询
select id,title,addtime from table1 as tab1,table2 as tab2,table3 as tab3 order by addtime
希望楼主使用union不要使用Union all,完全相同的重复数据对数据库来说没意义
SELECT DISTINCT * FROM ( SELECT a.id,a.title,a.addtime from table1 union ALL SELECT id,title,addtime from table2 union ALL SELECT id,title,addtime from table3 )A ORDER BY A.addtime DESC
union SELECT id,title,addtime from table2
union SELECT id,title,addtime from table3
order by a.addtime
union会把内容相同的过滤掉
union all SELECT id,title,addtime from table2
union SELECT id,title,addtime from table3
order by addtime
union all SELECT id,title,addtime from table2
union all SELECT id,title,addtime from table3
order by addtime
或者如果有关联的花就用联合查询
(
SELECT a.id,a.title,a.addtime from table1
union ALL
SELECT id,title,addtime from table2
union ALL
SELECT id,title,addtime from table3
)A
ORDER BY A.addtime DESC