可以用SQL实现同样的功能,就是麻烦了点。
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drop table t1;
drop table t2;
create table t1(id int primary key ,nickname varchar (20),playNum varchar (20));
create table t2(id int primary key ,nickname varchar (20),playNum varchar (20));
insert into t1 values (1,1,10);
insert into t1 values (2,2,20);
insert into t1 values (3,3,30);
insert into t2 values (1,1,10);
insert into t2 values (2,2,200);
insert into t2 values (3,33,300);
commit ;
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MySQL实现交集
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SELECT id, nickname, playNum, COUNT (*)
FROM ( SELECT id, nickname, playNum
FROM t1
UNION ALL
SELECT id, nickname, playNum
FROM t2
) a
GROUP BY id, nickname, playNum
HAVING COUNT (*) > 1
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MySQL实现差集
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SELECT t1.id, t1.nickname, t1.playNum
FROM t1 LEFT JOIN t2 ON t1.id = t2.id
WHERE t1.nickname != t2.nickname
OR t1.playNum != t2.playNum;
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