我正在编写一个我正在写的查询有困难。查询如下所示：
SELECT case when Year(LOAN_START_DATE) = 2010 then
max(LOAN_RES_BANK_CODE) else 0 end as '2010',
case when Year(LOAN_START_DATE) = 2011 then
max(LOAN_RES_BANK_CODE) else 0 end as '2011',
case when Year(LOAN_START_DATE) = 2012 then
max(LOAN_RES_BANK_CODE) else 0 end as '2012',
case when Year(LOAN_START_DATE) = 2013 then
max(LOAN_RES_BANK_CODE) else 0 end as '2013',
case when Year(LOAN_START_DATE) = 2014 then
max(LOAN_RES_BANK_CODE) else 0 end as '2014',
case when Year(LOAN_START_DATE) = 2015 then
max(LOAN_RES_BANK_CODE) else 0 end as '2015'
from LLOAN l
inner join LACMSTR c on c.ACCT_NUMBER = l.LOAN_ACCT_1 and c.SourceID = l.SourceID
where l.SourceID = 1
and c.ACCT_NUMBER = 1065
group by LOAN_START_DATE
这给出了以下输出：
2010 2011 2012 2013 2014 2015
----------------------------------
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
1 0 0 0 0 0
0 0 3 0 0 0
0 0 0 2 0 0
0 0 0 2 0 0
0 0 0 0 2 0
我希望输出只有一行，如下所示：
2010 2011 2012 2013 2014 2015
----------------------------------
1 0 3 2 2 0
我找到了一种方法，但这是一个真正丑陋而缓慢（相对而言）的查询：
select (select ISNULL(max(LOAN_RES_BANK_CODE),0)
from PfeDs.dbo.LLOAN t1, pfeds.dbo.LACMSTR t2
where t1.SourceID = t2.SourceID
and t2.SourceID = 1
and ACCT_NUMBER = LOAN_ACCT_1
and ACCT_NUMBER = 1065
and year(LOAN_START_DATE) = 2010) as '2010',
(select ISNULL(max(LOAN_RES_BANK_CODE),0)
from PfeDs.dbo.LLOAN t1, pfeds.dbo.LACMSTR t2
where t1.SourceID = t2.SourceID
and t2.SourceID = 1
and ACCT_NUMBER = LOAN_ACCT_1
and ACCT_NUMBER = 1065
and year(LOAN_START_DATE) = 2011) as '2011',
(select ISNULL(max(LOAN_RES_BANK_CODE),0)
from PfeDs.dbo.LLOAN t1, pfeds.dbo.LACMSTR t2
where t1.SourceID = t2.SourceID
and t2.SourceID = 1
and ACCT_NUMBER = LOAN_ACCT_1
and ACCT_NUMBER = 1065
and year(LOAN_START_DATE) = 2012) as '2012',
(select ISNULL(max(LOAN_RES_BANK_CODE),0)
from PfeDs.dbo.LLOAN t1, pfeds.dbo.LACMSTR t2
where t1.SourceID = t2.SourceID
and t2.SourceID = 1
and ACCT_NUMBER = LOAN_ACCT_1
and ACCT_NUMBER = 1065
and year(LOAN_START_DATE) = 2013) as '2013',
(select ISNULL(max(LOAN_RES_BANK_CODE),0)
from PfeDs.dbo.LLOAN t1, pfeds.dbo.LACMSTR t2
where t1.SourceID = t2.SourceID
and t2.SourceID = 1
and ACCT_NUMBER = LOAN_ACCT_1
and ACCT_NUMBER = 1065
and year(LOAN_START_DATE) = 2014) as '2014',
(select ISNULL(max(LOAN_RES_BANK_CODE),0)
from PfeDs.dbo.LLOAN t1, pfeds.dbo.LACMSTR t2
where t1.SourceID = t2.SourceID
and t2.SourceID = 1
and ACCT_NUMBER = LOAN_ACCT_1
and ACCT_NUMBER = 1065
and year(LOAN_START_DATE) = 2015) as '2015'
SQL不是我的强项。我应该以什么方式更改原始查询以获得我正在寻找的结果。我正在使用SQL Server 2014。
--------------------- ------------------ EDIT
Jarlh给出了一个很好的解决方案，以下查询给出了正确的输出：
select max(J10) as '2010', max(J11) as '2011', max(J12) '2012', max(J13) as '2013', max(J14) as '2014', max(J15) as '2015'
from (
SELECT case when Year(LOAN_START_DATE) = 2010 then max(LOAN_RES_BANK_CODE) else 0 end as J10,
case when Year(LOAN_START_DATE) = 2011 then max(LOAN_RES_BANK_CODE) else 0 end as J11,
case when Year(LOAN_START_DATE) = 2012 then max(LOAN_RES_BANK_CODE) else 0 end as J12,
case when Year(LOAN_START_DATE) = 2013 then max(LOAN_RES_BANK_CODE) else 0 end as J13,
case when Year(LOAN_START_DATE) = 2014 then max(LOAN_RES_BANK_CODE) else 0 end as J14,
case when Year(LOAN_START_DATE) = 2015 then max(LOAN_RES_BANK_CODE) else 0 end as J15
from pfeds.dbo.LLOAN l
inner join PfeDs.dbo.LACMSTR c on c.ACCT_NUMBER = l.LOAN_ACCT_1 and c.SourceID = l.SourceID
where l.SourceID = 1
and c.ACCT_NUMBER = 1065
group by LOAN_START_DATE) as test
答案 0 :(得分：2)
将原始查询用作派生表，然后MAX列：
select MAX('2010'), ...
from (
SELECT case when Year(LOAN_START_DATE) = 2010 then
max(LOAN_RES_BANK_CODE) else 0 end as '2010',
...
)
答案 1 :(得分：1)
如果要隐藏所有值为0的行，为什么不尝试在where子句中添加其中一行？
and max(LOAN_RES_BANK_CODE) > 0
或
and LOAN_RES_BANK_CODE >0