Question

请问以下可以用sql server语句实现吗？有table1和table2，table1中的数据有没有在table2中出现。如出现输出

table1:
id keyword
1 A
2 B
3 C
table2
id keyword
1 D
2 A
3 E
结果是：A

Answer 1

输出要什么？ID、keyboard都要？

试试这个
select keyboard from table1 where keyboard in (select keyboard from table2)

Answer 2

使用两个数据交集就可以了,IN的效率很低的
SELECT keyword FROM table1
INTERSECT
SELECT keyword FROM table2

Answer 3

select * from table2 where keyword in (select keyword from table1 )

Answer 4

select keyword from table1 where keyword in (select keyword from table2)

Answer 5

试试这个
select keyboard from table1 where keyboard in (select keyboard from table2)