Медленный запрос в SQL Server 2008 с использованием связанного сервера. На что я могу смотреть?

Question

Этот запрос первоначально был получен из программы VB6, доступ к таблицам MS Access, которые связаны с внешними базами данных через ODBC. Это займет около 3:30.

Теперь я установил окно SQL Server 2008 Express, чтобы оценить, как мы можем перейти на лучшую систему баз данных. Поэтому я устанавливаю связанный сервер на внешний сервер (мы называем его DWPROD), и когда я преобразовал запрос (сменил инструкции iif на случай) и запустил его, я разрешил ему работать 12 минут, и он до сих пор не заканчивается. Я новичок в SQL Server, так что я могу посмотреть, что происходит так долго? Любые предложения по ускорению этого? Любые ресурсы, рекомендуемые, чтобы я мог больше узнать об этом? Это простой запрос по сравнению с тем, что у нас есть, поэтому я снова удалю эту проблему.

Запрос:

SELECT [FISCAL_YEAR] AS FISCAL_YEAR, 
[Budgets].[dbo].[Departments].strdepentity AS ENTITY_CODE, 
[Budgets].[dbo].[Departments].depdiv1 AS DIVISION_CODE, 
FINANCIAL_DEPTID AS DEPTID, 
FUND_CODE, 
[CLASS_FLD] AS CLASS_CODE, 
[PROJECT_ID], 
[PROGRAM_CODE], 
[ACCOUNT] AS ACCOUNT_CODE, 
CASE 
    WHEN [ACCOUNT] in ('500020','520000','520220','520240') THEN 2 
    WHEN LEFT([ACCOUNT],1)='5' THEN 1 
    WHEN Left([ACCOUNT],1)='6' THEN 3 
    WHEN Left([ACCOUNT],1)='7' THEN 4 
    WHEN Left([ACCOUNT],1)='8' THEN 5 
    ELSE 0 
    END AS ACCT_GRP_CODE, 
Sum([BUDGET_AMOUNT]) AS GL_BUD_AMT, 
Sum([ENCUMBRANCE_AMOUNT]) AS GL_ENC_AMT, 
Sum([EXPENDITURE_AMOUNT]) AS GL_EXP_AMT, 
CASE 
    WHEN Left([CLASS_FLD],2)='12' THEN 0 
    WHEN Left([CLASS_FLD],3)='113' THEN 3 
    WHEN Left([CLASS_FLD],3)='112' THEN 14 
    WHEN Left([CLASS_FLD],3)='115' THEN 10 
    WHEN Left([CLASS_FLD],3)='116' THEN 13 
    WHEN Left([CLASS_FLD],3)='117' THEN 12 
    WHEN Left([CLASS_FLD],3)='118' THEN 11 
    WHEN Left([CLASS_FLD],2)='13' THEN 2 
    WHEN Left([CLASS_FLD],2)='14' THEN 3 
    WHEN Left([CLASS_FLD],1)='4' THEN 4 
    WHEN Left([CLASS_FLD],1)='6' THEN 6 
    ELSE 9 
    END AS FUND_SOURCE 

FROM [DWPROD]..[DISC].[PS_LEDGER_DETAIL] LEFT JOIN [Budgets].[dbo].[Departments] ON FINANCIAL_DEPTID=[Budgets].[dbo].[Departments].deporg 
WHERE ((([BUDGET_PERIOD])='2010') And (([ACCOUNTING_PERIOD]) Between 1 And 12)) 


GROUP BY 
[FISCAL_YEAR], 
[Budgets].[dbo].[Departments].strdepentity, [Budgets].[dbo].[Departments].depdiv1, 
[FINANCIAL_DEPTID], 
FUND_CODE, 
[CLASS_FLD], 
[PROJECT_ID], 
[PROGRAM_CODE], 
[ACCOUNT], 
CASE 
    WHEN [ACCOUNT] in ('500020','520000','520220','520240') THEN 2 
    WHEN LEFT([ACCOUNT],1)='5' THEN 1 
    WHEN Left([ACCOUNT],1)='6' THEN 3 
    WHEN Left([ACCOUNT],1)='7' THEN 4 
    WHEN Left([ACCOUNT],1)='8' THEN 5 
    ELSE 0 
    END, 
    CASE 
    WHEN Left([CLASS_FLD],2)='12' THEN 0 
    WHEN Left([CLASS_FLD],3)='113' THEN 3 
    WHEN Left([CLASS_FLD],3)='112' THEN 14 
    WHEN Left([CLASS_FLD],3)='115' THEN 10 
    WHEN Left([CLASS_FLD],3)='116' THEN 13 
    WHEN Left([CLASS_FLD],3)='117' THEN 12 
    WHEN Left([CLASS_FLD],3)='118' THEN 11 
    WHEN Left([CLASS_FLD],2)='13' THEN 2 
    WHEN Left([CLASS_FLD],2)='14' THEN 3 
    WHEN Left([CLASS_FLD],1)='4' THEN 4 
    WHEN Left([CLASS_FLD],1)='6' THEN 6 
    ELSE 9 
    END 
HAVING (((FISCAL_YEAR)=2010) 
AND ((FINANCIAL_DEPTID) Between '100' And '999') 
AND ((ACCOUNT) Between '500000' And '899999')) 
ORDER BY [FINANCIAL_DEPTID], [CLASS_FLD], [PROJECT_ID], [ACCOUNT] 

Я знаю, что это долго. Спасибо, что посмотрели.

Answer 1

Я переписал ваш запрос:.

WITH ledger_detail AS (
     SELECT pld.fiscal_year, 
      pld.financial_deptid AS DEPTID, 
      pld.fund_code, 
      pld.class_fld AS CLASS_CODE, 
      pld.project_id, 
      pld.program_code, 
      CASE 
       WHEN pld.account IN ('500020','520000','520220','520240') THEN 2 
       WHEN LEFT(pld.account,1) = '5' THEN 1 
       WHEN LEFT(pld.account,1) = '6' THEN 3 
       WHEN LEFT(pld.account,1) = '7' THEN 4 
       WHEN LEFT(pld.account,1) = '8' THEN 5 
       ELSE 0 
      END AS ACCT_GRP_CODE, 
      pld.budget_amount, 
      pld.encumbrance_amount, 
      pld.expenditure_amount, 
      pld.account AS ACCOUNT_CODE, 
      CASE 
       WHEN LEFT(pld.class_fld, 2) ='12' THEN 0 
       WHEN LEFT(pld.class_fld, 3)='113' THEN 3 
       WHEN LEFT(pld.class_fld, 3)='112' THEN 14 
       WHEN LEFT(pld.class_fld, 3)='115' THEN 10 
       WHEN LEFT(pld.class_fld, 3)='116' THEN 13 
       WHEN LEFT(pld.class_fld, 3)='117' THEN 12 
       WHEN LEFT(pld.class_fld, 3)='118' THEN 11 
       WHEN LEFT(pld.class_fld, 2)='13' THEN 2 
       WHEN LEFT(pld.class_fld, 2)='14' THEN 3 
       WHEN LEFT(pld.class_fld, 1)='4' THEN 4 
       WHEN LEFT(pld.class_fld, 1)='6' THEN 6 
       ELSE 9 
      END AS FUND_SOURCE 
     FROM [DWPROD]..[DISC].[PS_LEDGER_DETAIL] pld 
     WHERE pld.budget_period = '2010' 
     AND pld.accounting_period BETWEEN 1 AND 12 
     AND pld.fiscal_year = 2010 
     AND pld.financial_deptid BETWEEN '100' AND '999' 
     AND pld.account BETWEEN '500000' AND '899999') 
    SELECT x.fiscal_year, 
      y.strdepentity AS ENTITY_CODE, 
      y.depdiv1 AS DIVISION_CODE, 
      x.deptid, 
      x.fund_code, 
      x.class_code, 
      x.project_id, 
      x.program_code, 
      x.acct_grp_code, 
      SUM(x.budget_amount) AS GL_BUD_AMT, 
      SUM(x.encumbrance_amount) AS GL_ENC_AMT, 
      SUM(x.expenditure_amount) AS GL_EXP_AMT, 
      x.account AS ACCOUNT_CODE, 
      x.fund_source 
    FROM ledger_detail x 
LEFT JOIN [Budgets].[dbo].[Departments] y ON y.deporg = x.financial_deptid  
GROUP BY x.fiscal_year, y.strdepentity, y.depdiv1, x.deptid, x.fund_code, x.class_code, x.project_id, x.program_code, x.acct_grp_code 
ORDER BY x.financial_deptid, x.class_fld, x.project_id, x.account 

Даже если у вас есть индексы [DWPROD] .. [DISC] [PS_LEDGER_DETAIL] s account и class_fld, использование функции (LEFT) на них они не могут использоваться для этого запроса.

Кроме того, вы включаете критерии фильтра в предложение HAVING, а не в пункт WHERE.

UPDATE: Non-CTE Эквивалент

SELECT x.fiscal_year, 
      y.strdepentity AS ENTITY_CODE, 
      y.depdiv1 AS DIVISION_CODE, 
      x.deptid, 
      x.fund_code, 
      x.class_code, 
      x.project_id, 
      x.program_code, 
      x.acct_grp_code, 
      SUM(x.budget_amount) AS GL_BUD_AMT, 
      SUM(x.encumbrance_amount) AS GL_ENC_AMT, 
      SUM(x.expenditure_amount) AS GL_EXP_AMT, 
      x.account AS ACCOUNT_CODE, 
      x.fund_source 
    FROM (SELECT pld.fiscal_year, 
        pld.financial_deptid AS DEPTID, 
        pld.fund_code, 
        pld.class_fld AS CLASS_CODE, 
        pld.project_id, 
        pld.program_code, 
        CASE 
        WHEN pld.account IN ('500020','520000','520220','520240') THEN 2 
        WHEN LEFT(pld.account,1) = '5' THEN 1 
        WHEN LEFT(pld.account,1) = '6' THEN 3 
        WHEN LEFT(pld.account,1) = '7' THEN 4 
        WHEN LEFT(pld.account,1) = '8' THEN 5 
        ELSE 0 
        END AS ACCT_GRP_CODE, 
        pld.budget_amount, 
        pld.encumbrance_amount, 
        pld.expenditure_amount, 
        pld.account AS ACCOUNT_CODE, 
        CASE 
        WHEN LEFT(pld.class_fld, 2) ='12' THEN 0 
        WHEN LEFT(pld.class_fld, 3)='113' THEN 3 
        WHEN LEFT(pld.class_fld, 3)='112' THEN 14 
        WHEN LEFT(pld.class_fld, 3)='115' THEN 10 
        WHEN LEFT(pld.class_fld, 3)='116' THEN 13 
        WHEN LEFT(pld.class_fld, 3)='117' THEN 12 
        WHEN LEFT(pld.class_fld, 3)='118' THEN 11 
        WHEN LEFT(pld.class_fld, 2)='13' THEN 2 
        WHEN LEFT(pld.class_fld, 2)='14' THEN 3 
        WHEN LEFT(pld.class_fld, 1)='4' THEN 4 
        WHEN LEFT(pld.class_fld, 1)='6' THEN 6 
        ELSE 9 
        END AS FUND_SOURCE 
      FROM [DWPROD]..[DISC].[PS_LEDGER_DETAIL] pld 
      WHERE pld.budget_period = '2010' 
       AND pld.accounting_period BETWEEN 1 AND 12 
       AND pld.fiscal_year = 2010 
       AND pld.financial_deptid BETWEEN '100' AND '999' 
       AND pld.account BETWEEN '500000' AND '899999') x 
LEFT JOIN [Budgets].[dbo].[Departments] y ON y.deporg = x.financial_deptid  
GROUP BY x.fiscal_year, y.strdepentity, y.depdiv1, x.deptid, x.fund_code, x.class_code, x.project_id, x.program_code, x.acct_grp_code 
ORDER BY x.financial_deptid, x.class_fld, x.project_id, x.account