求 sql话语

求 sql语句
我的表的列名 id type type1 b1 b2 c1 c2
我想是type =A tyep1=1 的时候取 b1的值
我想是type =A tyep1=2的时候取 b2的值
我想是type =B tyep1=1的时候取 c1的值
我想是type =B tyep1=2的时候取 c2的值

[解决办法]

SQL code

select   case     when type='A' then       case         when type1=1 then b1        when type1=2 then b2      end    when type='B' then      case         when type1=1 then c1        when type1=2 then c2      end  endfrom tb
[解决办法]
SQL code
select *,       case when type ='A' and tyep1=1 then b1            when type ='A' and tyep1=2 then b2            when type ='B' and tyep1=1 then c1            when type ='B' and tyep1=2 then c2       end from [表]
[解决办法]
SQL code
create table test([id] int,[type] varchar(10),[type1] varchar(10),[b1] varchar(10),[b2] varchar(10),[c1] varchar(10),[c2] varchar(10))goinsert testselect 1,'A','1','a','a','a','a' union allselect 2,'B','2','b','a','c','d' union allselect 3,'A','2','c','e','a','d' union allselect 4,'B','1','g','a','a','e'select * from testdeclare @type varchar(10),@type1 varchar(10)set @type='B'set @type1='1'declare @sql varchar(max)select @sql=isnull(@sql,'')+' (case when [type]=''A'' and [type1]=''1'' then b1 when [type]=''A'' and [type1]=''2'' then b2 when [type]=''B'' and [type1]=''1'' then c1 when [type]=''B'' and [type1]=''2'' then b2 end) as val'print @sqlexec('select id,[type],[type1],'+@sql+' from test order by [type],[type1]' )drop table test(4 row(s) affected)id          type       type1      b1         b2         c1         c2----------- ---------- ---------- ---------- ---------- ---------- ----------1           A          1          a          a          a          a2           B          2          b          a          c          d3           A          2          c          e          a          d4           B          1          g          a          a          e(4 row(s) affected) (case when [type]='A' and [type1]='1' then b1 when [type]='A' and [type1]='2' then b2 when [type]='B' and [type1]='1' then c1 when [type]='B' and [type1]='2' then b2 end) as valid          type       type1      val----------- ---------- ---------- ----------1           A          1          a3           A          2          e4           B          1          a2           B          2          a(4 row(s) affected)