我具体就是想得到这样的结果:SELECT orderId,sellerId,buyerId, (SELECT name FROM ts_user WHERE id=sellerId)sellerName, (SELECT name FROM ts_user WHERE id=buyerId)buyerName FROM ts_order因为实际的表中的列相当多,所以用子查询的话怕遇到效率问题,想问问还有没有其他的办法
SELECT a.orderId,a.sellerId,a.buyerId,b.name as sellerName,c.name as buyerName FROM ts_order a LEFT JOIN ts_user b ON a.sellerID=b.ID LEFT JOIN ts_user c ON a.buyerID=c.ID
(SELECT name FROM ts_user WHERE id=sellerId)sellerName,
(SELECT name FROM ts_user WHERE id=buyerId)buyerName
FROM ts_order因为实际的表中的列相当多,所以用子查询的话怕遇到效率问题,想问问还有没有其他的办法
FROM ts_order a
LEFT JOIN ts_user b ON a.sellerID=b.ID
LEFT JOIN ts_user c ON a.buyerID=c.ID