mysql a,b,c 三个表的 left join

[liuhengwinner]

   select a.ttc,convert(a.oilgunno,SIGNED) as oilgunno,
  a.cardno, a.machineoilno,a.oilno,b.oilname,
  DATE_FORMAT(a.takedate, '%Y-%m-%d %H:%i:%s') as takedate
  from srs_bm_oilvouch a
  LEFT JOIN srs_system_oiltype b ON a.oilno = b.oilno,

还有C表还要 左连接和 a 表，应该怎么样，谢谢

[liuhengwinner]

就是3个表的左连接

[zjcxc]

和 left join b 一样，加在后面就行

[qq_30635781]

在后面加就行了，on 的条件给a表的条件就OK了

[qq_30635781]

引用 1 楼 liuhengwinner 的回复:

就是3个表的左连接

select a.ttc,convert(a.oilgunno,SIGNED) as oilgunno, a.cardno, a.machineoilno,a.oilno,b.oilname, DATE_FORMAT(a.takedate, '%Y-%m-%d %H:%i:%s') as takedate from srs_bm_oilvouch a LEFT JOIN srs_system_oiltype b ON a.oilno = b.oilno LEFT JOIN C表 c ON a.XXX = c.XXX

[小野马1209]

LEFT JOIN C ON C.oilno=A.oilno

[Andy__Huang]

select a.ttc,convert(a.oilgunno,SIGNED) as oilgunno,
	a.cardno, a.machineoilno,a.oilno,b.oilname,
	DATE_FORMAT(a.takedate, '%Y-%m-%d %H:%i:%s') as takedate
from srs_bm_oilvouch a
LEFT JOIN srs_system_oiltype b ON a.oilno = b.oilno,
LEFT JOIN 第三个表 c ON a.oilno = c.oilno

[Rotel-刘志东]

select a.ttc,convert(a.oilgunno,SIGNED) as oilgunno, a.cardno, a.machineoilno,a.oilno,b.oilname, DATE_FORMAT(a.takedate, '%Y-%m-%d %H:%i:%s') as takedate from srs_bm_oilvouch a LEFT JOIN srs_system_oiltype b ON a.oilno = b.oilno, LEFT JOIN c on a.oilno=c.oilno