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多表联合查询多个名相同时如何解决

多表联合查询多个名相同时如何解决

作者: 小牛长成记 | 来源:发表于2018-12-20 09:43 被阅读0次

    多张表联合查询时,多张表中包含相同字段,联合查询后相同的字段将会出现以下效果:
    其中state,cid ,csid字段为重复字段,可以看出后面再次查询出的重复字段都加了尾缀1


    QQ截图20181220093711.png

    解决办法可以将重复字段起别名解决:

    QQ截图20181220094051.png

    附加查询语句:

    select product.csid as pcsid ,product.state as pstate,product.date as pdate,product.market_price,
                    product.pdesc,product.pid as ppid,product.pname,product.shop_price,product.stock,
                 category_floor.state as cstate ,category_floor.cid as cfcid ,category_floor.cname,category_floor.img,category_floor.state as cfstate ,
                    category_second_floor.cid as csfcid ,category_second_floor.csid,category_second_floor.csname,category_second_floor.state as csfstate,
                    image.date as imgdate ,image.image_id,image.`name`  ,image.old_name,image.path,image.pid as imgpid ,image.state as imgstate
                    
                    from category_floor
            left join category_second_floor
            on category_floor.cid = category_second_floor.cid
            left join product
            on category_second_floor.csid = product.csid
            left join image
            on product.pid = image.pid
    

     select  product.csid ,product.state as pstate,product.date as pdate,product.market_price,
                    product.pdesc,product.pid ,product.pname,product.shop_price,product.stock,
                    category_floor.state as cstate ,category_floor.cid ,category_floor.cname,category_floor.img,category_floor.state as cfstate ,
                    category_second_floor.cid  ,category_second_floor.csid,category_second_floor.csname,category_second_floor.state as csfstate,
                    image.date as imgdate ,image.image_id,image.`name`  ,image.old_name,image.path,image.pid ,image.state as imgstate
    
                    from category_floor
                    left join category_second_floor
                    on category_floor.cid = category_second_floor.cid
                    left join product
                    on category_second_floor.csid = product.csid
                    left join image
                    on product.pid = image.pid
    
    
    

    
    select  *
        from category_floor
            left join category_second_floor
            on category_floor.cid = category_second_floor.cid
            left join product
            on category_second_floor.csid = product.csid
            left join image
            on product.pid = image.pid

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