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mysql> select * from user where city='beijing' or skill='pugong';
+------+---------+---------+--------+----------+
| uid | city | company | skill | zhengshu |
+------+---------+---------+--------+----------+
| 1 | beijing | a | baoan | benke |
| 1 | nanjing | b | pugong | benke |
| 2 | shanxi | b | pugong | benke |
+------+---------+---------+--------+----------+
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SQL code:
select distinct a.uid
from user a inner join user b on a.uid=b.uid
where a.city='beijing' and b.skill='pugong'
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