mysql在当前行增加值并为每组重置

Question

我有一个表，其中包含客户的默认契约(Contract)编号，我尝试添加每个契约(Contract)的部分内容。在本例中，我使用 Number 列作为组合 contract id 与每个客户端的连续行数。

这是查询

select '0' as Id, CONCAT(ea.Id, '-', count(loc.Id)) as Number, loc.* 
from EnergyAgreement ea 
left join (
    select 1545 as Id, 301005 as custId UNION ALL
    select 2454 as Id, 301005 as custId UNION ALL
    select 3654 as Id, 301005 as custId UNION ALL
    select 1546 as Id, 301008 as custId UNION ALL
    select 2454 as Id, 301008 as custId             
) as loc ON loc.custId = ea.CustomerId 
where ea.CustomerId IN (301005, 301008)
group by loc.Id, loc.custId  
order by Number ASC`

这是错误的结果(参见Number列)

"Id" "Number" "Id"   "custId"
"0"  "77-1"   "1545" "301005"
"0"  "77-1"   "2454" "301005"
"0"  "77-1"   "3654" "301005"
"0"  "81-1"   "2454" "301008"
"0"  "81-1"   "1546" "301008"

如何构建查询以连续递增 Number 列，直到下一个 customer ID 出现，以便我可以获得如下正确的设置结果？:

"Id" "Number" "Id"   "custId"
"0"  "77-1"   "1545" "301005"
"0"  "77-2"   "2454" "301005"
"0"  "77-3"   "3654" "301005"
"0"  "81-1"   "2454" "301008"
"0"  "81-2"   "1546" "301008"

Answer 1

只需在 loc 子查询中添加所需的值即可:

select '0' as Id, CONCAT(ea.Id, '-', loc.n) as Number, loc.id, loc.custId
from EnergyAgreement ea left join
     (select 1545 as Id, 301005 as custId, 1 as n UNION ALL
      select 2454 as Id, 301005 as custId, 2 UNION ALL
      select 3654 as Id, 301005 as custId, 3 UNION ALL
      select 1546 as Id, 301008 as custId, 1 UNION ALL
      select 2454 as Id, 301008 as custId, 2          
     ) loc
     on loc.custId = ea.CustomerId 
where ea.CustomerId IN (301005, 301008)
group by loc.Id, loc.custId, loc.n 
order by Number ASC`