mysql的ON DUPLICATE KEY的用法

1. 直接更改字段值

Insert into table(code,name)
values('a','aa')
ON DUPLICATE KEY
update updateTime=now()

2. 根據原值修改當前值

傳入參數 #{step}

INSERT INTO  table(code,version) 
VALUES ('a',(@newVersion:=#{step})) 
ON DUPLICATE KEY UPDATE 
version=(@newVersion:=version+#{step});

3. 批量修改

-- bean_name爲唯一字段        
INSERT INTO job (bean_name,params,cron_expression)
        select  bean_name,params,cron_expression
        from m_job
        where  id=#{dtmJobId}
        ON DUPLICATE KEY UPDATE
        cron_expression=values(cron_expression),
        params=values(params)