mysql update jion ¶à±í ¸ßÊÖÀ´¿´¿´

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a±í:
aid
ascore
*******************************************

b±í:
bid
bpei

********************************************

c±í:
bid
aid
cscore

Âé·³¿ªÊ¼ÁË:ÈçºÎʵÏÖÕâ¸öupdate
ascore +=  bpei * cscore

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UPDATE C from C INNER JOIN A ON C.AID=A.AID INNER JOIN  B ON C.BID=C.BID
SET C.ascoreB.=bpei * A.cscore

---

ascore +=  bpei * cscore£ºÀÛ¼Ó£¿+£½Ê²Ã´Òâ˼£¿

---

SQL code:
update c inner jon a on c.aid=a.aid inner join b on c.bid=b.bid
set c.ascore=c.ascore+a.cscore+b.bpei;

---

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ascore +=  bpei * cscore£ºÀÛ¼Ó£¿+£½Ê²Ã´Òâ˼£¿

+=  ÕâÊÇCÔËËã·û

x += y  ==>> x = x + y

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UPDATE C from C INNER JOIN A ON C.AID=A.AID INNER JOIN  B ON C.BID=b.BID
SET C.ascore= C.ascore+b.bpei * c.cscore

---

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SQL codeupdate cinner jon aon c.aid=a.aidinnerjoin bon c.bid=b.bidset c.ascore=c.ascore+a.cscore+b.bpei;

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You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to

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