Database|MySQL数据库语句中设临时变量

set @cat_id=0; select @cat_id:=cat_id from category where cat_name='shoes'; update products set shop_price=shop_price+7 where cat_id=@cat_id; update products set market_price=market_price+7 where cat_id=@cat_id;

【Database|MySQL数据库语句中设临时变量】 @cat_id为临时变量,select @cat_id:=cat_id from category where cat_name='shoes'将查询结果存放到@cat_id中,update语句中用到了@cat_id

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