1。最近在做项目的时候,遇到这样的一个问题,就是我每做完一件事情,都要更新一下统计表,然而要更新统计表,就要根据主键去统计表里面去查询是否已经有这样的一条记录,如果有那么就更新,如果没有那么就插入一条记录,开始我就是这么干的,结果被老大给否
1。最近在做项目的时候,遇到这样的一个问题,就是我每做完一件事情,都要更新一下统计表,然而要更新统计表,就要根据主键去统计表里面去查询是否已经有这样的一条记录,如果有那么就更新,如果没有那么就插入一条记录,开始我就是这么干的,结果被老大给否决了,他说可以用on duplicate key update去做。下面就实际操作一下吧:表结构:
+-----------+---------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+---------+------+-----+---------+-------+
| player_id | int(11) | NO | PRI | NULL | |
| count | int(11) | YES | | NULL | |
+-----------+---------+------+-----+---------+-------+
2 rows in set (0.01 sec)
select * from player_count where player_id = 1;//查询统计表中是否有记录 insert into player_count(player_id,count) value(1,1);//没有记录就执行insert 操作 update player_count set count = count+1 where player_id = 1;//有记录就执行update操作
insert into player_count(player_id,count) value(1,1) on duplicate key update count=count+1;

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