Improving SQL Code

Question

I'm using Pervasive SQL. I have the following UNION of mulitple SQL statements. Is there a way to clean this up, especially the Pay Date an the Loc No fields that are selected in each statement. Is there a way to pull this out and have only one place to need to change those two fields?

(
    SELECT 
    '23400' as Gl_Number,
        y.Plan as Description,
        0 as Hours,
        ROUND(SUM(Ee_Curr),2) as Debit,
        0 as Credit
    FROM "PR_YLOC" y
    LEFT JOIN PR_SUMM s ON (s.Summ_No = y.Summ_No)
    WHERE y.Loc_No = 1041
    AND s.Pay_Date = '2010-04-02'
    AND y.Code IN (100, 105, 110)
    AND y.Type = 3
    GROUP BY y.Plan
) UNION (
    SELECT 
    '72000' as Gl_Number,
        y.Plan,
        0,
        ROUND(SUM(Er_Curr),2),
        0
    FROM "PR_YLOC" y
    LEFT JOIN PR_SUMM s ON (s.Summ_No = y.Summ_No)
    WHERE y.Loc_No = 1041
    AND s.Pay_Date = '2010-04-02'
    AND y.Code IN (100, 105, 110)
    AND y.Type = 3
    GROUP BY y.Plan
) UNION (
SELECT '24800',
       c.Plan,
       0,
       ROUND(SUM(Ee_Amt),2),
       0
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code = 100
    GROUP BY c.Plan
) UNION (
SELECT '24800',
       c.Plan,
       0,
       0,
       ROUND(SUM(Ee_Amt),2)
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code = 115
    GROUP BY c.Plan
) UNION (
SELECT '24150',
       c.Plan,
       0,
       0,
       ROUND(SUM(Ee_Amt),2)    
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code = 241
    GROUP BY c.Plan
) UNION (
SELECT '24150',
       c.Plan,
       0,
       ROUND(SUM(Ee_Amt),2),
       0
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code = 239
    GROUP BY c.Plan
) UNION (
SELECT '24120',
       c.Plan,
       0,
       ROUND(SUM(Ee_Amt),2),
       0
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code = 230
    GROUP BY c.Plan
) UNION (
SELECT '24100',
       c.Plan,
       0,
       ROUND(SUM(Ee_Amt),2),
       0
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code = 225
    GROUP BY c.Plan
) UNION (
SELECT '23800',
       c.Plan,
       0,
       ROUND(SUM(Ee_Amt),2),
       0
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code = 245
    GROUP BY c.Plan
) UNION (
select m.Def_Dept as Gl_Number, t.Short_Desc,
    (SELECT SUM(Hours) FROM pr_earn en WHERE en.Loc_No = e.Loc_No AND en.Emp_No = e.Emp_No AND en.Pay_Date = e.Pay_Date AND en.Pay_Code = e.Pay_Code) as Hours,
    (SELECT SUM(Pay_Amt) FROM pr_earn en WHERE en.Loc_No = e.Loc_No AND en.Emp_No = e.Emp_No AND en.Pay_Date = e.Pay_Date AND en.Pay_Code = e.Pay_Code) as Debit,
    0
from pr_earn e
left join pr_mast m on (e.Loc_No = m.Loc_No and e.Emp_No = m.Emp_No)
left join pr_ptype t ON (t.Code = e.Pay_Code)
where e.loc_no = 1041 and e.pay_date = '2010-04-02'
group by m.Def_Dept, t.Short_Desc
)

Thanks

Answer 1

Instead of many selects with almost the same filter criteria (difference at "AND Code = ..."), you could replace with only one select with filter criteria AND Code IN (..., ..., ...).

Answer 2

Seems like you're trying to have more maintainability without affecting performance. I don't know this platform, but I would guess that you could move one where clause to the end, with your Unions as a subquery, and that the query optimzer might be able to figure out to apply the where conditions in each unioned set.

Answer 3

You can use a case statement for this. E.g.:

SELECT  
'23400' as Gl_Number, 
    y.Plan as Description, 
    0 as Hours, 
    ROUND(SUM(Ee_Curr),2) as Debit, 
    0 as Credit 
FROM "PR_YLOC" y 
LEFT JOIN PR_SUMM s ON (s.Summ_No = y.Summ_No) 
WHERE y.Loc_No = 1041 
AND s.Pay_Date = '2010-04-02' 
AND y.Code IN (100, 105, 110) 
AND y.Type = 3 
GROUP BY y.Plan 
UNION
SELECT  
'72000' as Gl_Number, 
    y.Plan, 
    0, 
    ROUND(SUM(Er_Curr),2), 
    0 
FROM "PR_YLOC" y 
LEFT JOIN PR_SUMM s ON (s.Summ_No = y.Summ_No) 
WHERE y.Loc_No = 1041 
AND s.Pay_Date = '2010-04-02' 
AND y.Code IN (100, 105, 110) 
AND y.Type = 3 
GROUP BY y.Plan 
UNION
SELECT case Code 
            when Code in (100,115) then'24800'
            when Code in (241, 239) then'24150'
            when Code = 230 then'24120'
            when Code = 225 then'24100'
            when Code = 245 then'23800'
        end, 
       c.Plan, 
       0, 
       ROUND(SUM(Ee_Amt),2), 
       0 
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code in (100,115,241,239,230,225,245)
    GROUP BY c.Plan 
select m.Def_Dept as Gl_Number, t.Short_Desc, 
    (SELECT SUM(Hours) FROM pr_earn en WHERE en.Loc_No = e.Loc_No AND en.Emp_No = e.Emp_No AND en.Pay_Date = e.Pay_Date AND en.Pay_Code = e.Pay_Code) as Hours, 
    (SELECT SUM(Pay_Amt) FROM pr_earn en WHERE en.Loc_No = e.Loc_No AND en.Emp_No = e.Emp_No AND en.Pay_Date = e.Pay_Date AND en.Pay_Code = e.Pay_Code) as Debit, 
    0 
from pr_earn e 
left join pr_mast m on (e.Loc_No = m.Loc_No and e.Emp_No = m.Emp_No) 
left join pr_ptype t ON (t.Code = e.Pay_Code) 
where e.loc_no = 1041 and e.pay_date = '2010-04-02' 
group by m.Def_Dept, t.Short_Desc 

Answer 4

Could you replace the middle set of SELECT statements with something like this?

) UNION (
SELECT CASE Code
         WHEN 100 THEN '24800'
         WHEN 115 THEN '24800',
         WHEN 241 THEN '24150'
         WHEN 239 THEN '24150',
         WHEN 230 THEN '24120',
         WHEN 225 THEN '24100'
         WHEN 245 THEN '23800',
       END,
       c.Plan,
       0,
       ROUND(SUM(Ee_Amt),2),
       0
    FROM "PR_CDED" c WHERE Pay_Date = '2010-04-02' AND Loc_No = 1041 AND Code IN (100, 115, 241, 239, 230, 225, 245)
    GROUP BY c.Plan
) UNION (

That's a T-SQL CASE statement, but I'm sure Oracle PL/SQL has something similar.