bea*_*end 5 mysql sql union select
如果我有一个简单的联盟
select name, phone from users union select name, phone from vendors;
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有没有办法将表名添加到结果中?
而不是
+--------+-------+
| name | phone |
+--------+-------+
| Jim | 123...|
| Macy's | 345...|
+--------+-------+
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我明白了
+--------+-------+---------+
| name | phone | table |
+--------+-------+---------+
| Jim | 123...| users |
| Macy's | 345...| vendors |
+--------+-------+---------+
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Rom*_*kar 20
select name, phone, 'users' as table_name from users
union
select name, phone, 'vendors' as table_name from vendors;
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更好的解决方案是使用union all,因此服务器不会检查不同的值
select name, phone, 'users' as table_name from users
union all
select name, phone, 'vendors' as table_name from vendors;
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