sql - 如何将这两条SQL语句结合起来呢？

Question

我有 2 个 SQL 查询，它们都获取不同 ID 的计数。

select @cntCM_CMQ = count(*)
from dbo.CaseWorkflow cw 
join vew_CasePersonnelSystemIDs vcps on cw.ID_Case = vcps.ID_Case
join dbo.WorkflowStates ws on ws.ID_WorkflowState = cw.ID_WorkflowState
where CMSUID = @nSUID and ws.ID_WorkflowType = 3    -- CMQ

select @cntCM_PRWK = count(*)
from dbo.CaseWorkflow cw 
join vew_CasePersonnelSystemIDs vcps on cw.ID_Case = vcps.ID_Case
join dbo.WorkflowStates ws on ws.ID_WorkflowState = cw.ID_WorkflowState
where CMSUID = @nSUID and ws.ID_WorkflowType = 1    -- PAPERWORK

似乎我应该能够将它们组合成一个单一的选择(也许使用 CASE 语句)，但我似乎无法破解它。

Answer 1

是这样的吗？

select sum(case when ws.ID_WorkflowType = 1 then 1 else 0 end) as cntCM_PRWK
     , sum(case when ws.ID_WorkflowType = 3 then 1 else 0 end) as cntCM_CMQ
from dbo.CaseWorkflow cw 
join vew_CasePersonnelSystemIDs vcps on cw.ID_Case = vcps.ID_Case
join dbo.WorkflowStates ws on ws.ID_WorkflowState = cw.ID_WorkflowState
where CMSUID = @nSUID