今天在写项目的时候，遇到了一个比价头疼的问题：

ifnull.............

No function matches the given name and argument types. You might need to add explicit type casts

 

现在公司用的是postgrepsql数据库，自己用navicat连接的，屁颠屁颠的还当是mysql的函数语法来用的，扣了半天，原来才发现，pg数据库中根本就没有ifnull这个函数，

可以使用COALESCE函数代替。

这是改正确之后的sql语句：

SELECT tt.NAME, tt.sex, tt.idcardtype, tt.idcard, tt.mobile
    , tt.birthday, tt.ID, tt.vipid, tt.cardno, tt.cardtypename
    , tt.cardtypecode, tt.gradetypename, tt.status, tt.TYPE, tt.changecardno
    , tt.changecardnoflag, tt.PASSWORD, tt.accountmoneytype, tt.networktype, tt.usertype
    , tt.money, tt.points, tt.couponcnt, tt.relatedcnt,
    COALESCE ( tt.comname, tt.unitname )   as  unitname,
    tt.refereecode,
      tt.insuretype, tt.starteffectdate, tt.endeffectdate, tt.uniagentcode, tt.unisaleschannel
    , tt.unisalesbusitype
FROM (
    SELECT vip.NAME, vip.sex, vip.idcardtype, vip.idcard, vip.mobile
        , vip.birthday, acc.ID, acc.vipid
        , CASE 
            WHEN acc.cardno IS NULL THEN acc.changecardno
            ELSE acc.cardno
        END AS cardno, acc.cardtypename, acc.cardtypecode, acc.gradetypename, acc.status
        , acc.TYPE, acc.changecardno, acc.changecardnoflag, acc.PASSWORD, acc.accountmoneytype
        , acc.networktype, acc.usertype, mon.money, mon.points
        , CASE 
            WHEN cp.couponcnt IS NULL THEN 0
            ELSE cp.couponcnt
        END AS couponcnt
        , (
            SELECT COUNT(0)
            FROM vip_accountrelated T
            WHERE T.vipid = vip.ID
                AND T.accountid = acc.ID
                AND T.dr = 0
        ) AS relatedcnt
        , (
            SELECT t1.unit_name::VARCHAR
            FROM up_org_unit t1, up_org_unit_ext t2
            WHERE t1.unit_id = t2.unit_id
                AND t2.unit_uncode = vip.unitid
        ) AS unitname
        , (
            SELECT t1.unit_name::VARCHAR
            FROM up_org_unit t1, up_org_unit_ext t2
            WHERE t1.unit_id = t2.unit_id
                AND t2.unit_uncode = acc.sendunitid
        ) AS comname, acc.refereecode, vip.insuretype, acc.starteffectdate, acc.endeffectdate
        , acc.uniagentcode, acc.unisaleschannel, acc.unisalesbusitype
    FROM VIP_ACCOUNT acc, VIP_INFO vip, VIP_ACCOUNTMONEY mon, (
            SELECT ac.accountid, COUNT(0) AS couponcnt
            FROM VIP_ACCOUNTCOUPON ac, VIP_COUPON cou
            WHERE ac.couponcode = cou.code
                AND cou.status = 1
                AND ac.dr = 0
                AND cou.dr = 0
            GROUP BY ac.accountid
        ) cp
    WHERE acc.vipid = vip.ID
        AND acc.ID = mon.ID
        AND acc.ID = cp.accountid
        AND acc.dr = 0
        AND vip.dr = 0
        AND mon.dr = 0
) tt
ORDER BY tt.usertype OFFSET ( ?- 1 ) * ? 
    LIMIT ?

推荐一个网址：产看pgsql常用的函数：

https://www.cnblogs.com/personblog/p/11042105.html