如何为每个有条件的分区应用row_number

Question

我想添加一个名为PLRowNo的列，它是每个凭证组中PL acttype的行号。我还希望每个凭证编号的编号从1开始。

这是的预期结果

| id | voucherID | actype | PLRowNo |
|----|-----------| -------|---------|
| 1  | voucher01 | BS     |         |
| 2  | voucher01 | PL     | 1       |
| 3  | voucher01 | BS     |         |
| 4  | voucher01 | PL     | 2       |
| 5  | voucher01 | PL     | 3       |
| 6  | voucher01 | BS     |         |       
| 7  | voucher01 | PL     | 4       |
| 8  | voucher01 | BS     |         |
| 9  | voucher01 | PL     | 5       |
| 10 | voucher02 | PL     |         |
| 11 | voucher02 | PL     | 1       |
| 12 | voucher02 | BS     |         |
| 13 | voucher02 | PL     | 2       |

这就是我尝试过的：

CREATE TABLE tbl_tmp (
id int not null primary key,
voucherID nvarchar(10) not null,
actype nvarchar(10) not null
);
insert into tbl_tmp(id,voucherID, actype)
values (1,'voucher01', 'BS'),
(2,'voucher01', 'PL'),
(3,'voucher01', 'BS'),
(4,'voucher01', 'PL'),
(5,'voucher01', 'PL'),
(6,'voucher01', 'BS'),
(7,'voucher01', 'PL'),
(8,'voucher01', 'BS'),
(9,'voucher01', 'PL'),
(10,'voucher02', 'PL'),
(11,'voucher02', 'PL'),
(12,'voucher02', 'BS'),
(13,'voucher02', 'PL')
select *,0 as PLRowNo into #tmp from tbl_tmp
declare @id int set @id=0
update #tmp
set @id= case when actype ='PL' then @id+1   else 0 end,
PLRowNo = case when actype='PL' then @id else 0 end
select * from #tmp

这个查询的问题是，如果前一行的类型是"BS"，即使在同一个凭证分区中，它也会从1(id:13(开始计数。我想在一张代金券内续借

这是错误的结果

| id | voucherID | actype | PLRowNo |
|----|-----------| -------|---------|
| 1  | voucher01 | BS     |         |
| 2  | voucher01 | PL     | 1       |
| 3  | voucher01 | BS     |         |
| 4  | voucher01 | PL     | 2       |
| 5  | voucher01 | PL     | 3       |
| 6  | voucher01 | BS     |         |       
| 7  | voucher01 | PL     | 4       |
| 8  | voucher01 | BS     |         |
| 9  | voucher01 | PL     | 5       |
| 10 | voucher02 | PL     |         |
| 11 | voucher02 | PL     | 1       |
| 12 | voucher02 | BS     |         |
| 13 | voucher02 | PL     | 1       |

Answer 1

您不需要临时表或古怪的更新，只需使用ROW_NUMBER即可

SELECT *,
PLRow_no = CASE WHEN actype = 'PL' THEN
ROW_NUMBER() OVER (PARTITION BY actype, voucherID ORDER BY id) 
END
FROM tbl_tmp
ORDER BY id;

db<gt；小提琴

Answer 2

请尝试一下。

select *,    
CASE
WHEN actype='PL' THEN CAST((select count(*) from tbl_tmp as t where actype='PL' and t.id<=tbl_tmp.id and  t.voucherID=tbl_tmp.voucherID )as VarChar(10))
ELSE ''
END
as PLRowNo     
from tbl_tmp