我有一张表里面两个字段LineNo和IfSave,LineNo为正整数,IfSave为'T' or 'F'
对数据的要求是,LineNo相同的记录有且只有一条IfSave='T',超过一条为'T'或者全部为'F'的即为不合格数据。
请问怎么筛选出不合格的数据?
用的数据库是Firebird。
对数据的要求是,LineNo相同的记录有且只有一条IfSave='T',超过一条为'T'或者全部为'F'的即为不合格数据。
请问怎么筛选出不合格的数据?
用的数据库是Firebird。
go
if OBJECT_ID('tbl')is not null
drop table tbl
go
create table tbl
(
[LineNo] int,
[IfSave] varchar(1)
)
go
insert into tbl
select 1,'T' union all
select 1,'T' union all
select 1,'T' union all
select 1,'F' union all
select 2,'T' union all
select 2,'F' union all
select 2,'F' union all
select 2,'F' union all
select 3,'T' union all
select 4,'F' union all
select 5,'T' union all
select 5,'T' union all
select 6,'F' select [LineNo] from(
select [LineNo],
sum( case when [IfSave]='T' then 1 else 0 end) as T,
sum( case when [IfSave]='F' then 1 else 0 end) as F
from tbl group by [LineNo])a
where T>1 or (T=0 and F>=1)
/*
LineNo
1
4
5
6
*/
from tab
where IfSave='T'
group by lineNo
having count(1)>1
union all
select lineNo,count(1)
from (select lineNo,IfSave
from tab group by lineNo,IfSave ) as t
where IfSave='F'
group by lineNo
having count(1)=1
select [LineNo],
sum( case when [IfSave]='T' then 1 else 0 end) as T
from tbl group by [LineNo]) a
where T>1 or T=0又用了几次,只要判断T>1 or T=0就可以了