Question

您好我有以下SQL查询

 Select catalogid , numitems, allitems - numitems ignoreditems
        from ( 
        select i.catalogid,
         sum(case when (ocardtype in ('PayPal','Sofort') OR
                        ocardtype in ('mastercard','visa') and
                        odate is not null) then numitems
                        else 0 end) numitems,
         sum(numitems) allitems 
        from orders o
        join oitems i on i.orderid=o.orderid
        join products T1 on T1.catalogid = i.catalogid
        group by i.catalogid
        ) X

在最后一个连接语句表中产品包含8列并且它们没有显示在结果查询中，我只能看到列catalogid，numitems和ignoreditems，所以我做错了，如果我必须选择那些列为了使它们出现我怎么能用这种语法来做呢？

Answer 1

Select catalogid , numitems, allitems - numitems ignoreditems, X.c1,X.c2,X.c3,X.c4,X.c5,X.c6,X.c7,X.c8
    from ( 
    select i.catalogid,
     sum(case when (ocardtype in ('PayPal','Sofort') OR
                    ocardtype in ('mastercard','visa') and
                    odate is not null) then numitems
                    else 0 end) numitems,
     sum(numitems) allitems ,
     T1.c1, T1.c2, T1.c3, T1.c4, T1.c5, T1.c6, T1.c7, T1.c8
    from orders o
    join oitems i on i.orderid=o.orderid
    join products T1 on T1.catalogid = i.catalogid
    group by i.catalogid, T1.c1, T1.c2, T1.c3, T1.c4, T1.c5, T1.c6, T1.c7, T1.c8
    ) X

Answer 2

您只是查询这三列。如果希望产品中的列显示在结果集中，只需将它们添加到select语句即可。您可以逐个添加它们，或者只添加T1。*来查询所有这些：

Select catalogid , numitems, allitems - numitems ignoreditems, X.columnName1, X.ColumnName2, X.*
from ( 
select i.catalogid,
sum(case when (ocardtype in ('PayPal','Sofort') OR
ocardtype in ('mastercard','visa') and
odate is not null) then numitems
else 0 end) numitems,
sum(numitems) allitems,
-- This
T1.ColumnName1, T1.ColumName2, ...
--- or this way
T1.*
from orders o
join oitems i on i.orderid=o.orderid
join products T1 on T1.catalogid = i.catalogid
group by i.catalogid
) X

SQL连接多个表，第3个表中的列未显示

2 个答案: