Improve INSERT INTO SELECT Query performance? - sql

Question

I am trying to improve old while loop query. So far tried this but it is still slow. Not sure may be SUM perform slow.
Old query (10 mins+)
ALTER PROCEDURE [dbo].[process_tax]
#userid VARCHAR(10),
#remark NVARCHAR(500),
#tdate DATE,
#roadno NVARCHAR(10),
#inst INT
AS
BEGIN
IF OBJECT_ID('tempdb..#tempProcess_tax_1') IS NOT NULL
DROP TABLE #tempProcess_tax_1
CREATE TABLE #tempProcess_tax_1
(
RowID INT IDENTITY(1, 1),
clid_ INT,
hlid_ INT,
holdinNo_ NVARCHAR(500),
holding_ NVARCHAR(50),
clientid_ NVARCHAR(500),
clientName_ NVARCHAR(500)
)
INSERT INTO #tempProcess_tax_1 (clid_, hlid_, holdinNo_, holding_, clientid_, clientName_)
SELECT
cl.clid AS clid_, cl.id AS hlid_, holdinNo, holding,
ClientID AS clientid_, ClientName AS clientName_
FROM
tx_holding AS cl
WHERE
cl.status = 1 AND cl.roadno = #roadno
AND cl.id IN (SELECT hlid FROM tx_asset WHERE asset IS NOT NULL)
AND cl.clid IN (SELECT id FROM tbl_client WHERE client_type = 'Non-Govt.')
AND cl.id NOT IN (SELECT hlid FROM tx_bill_pay
WHERE YEAR(date_month) = YEAR(#tdate)
AND hlid IS NOT NULL
GROUP BY hlid)
DECLARE #NumberRecords_1 INT, #RowCounter_1 INT
SET #NumberRecords_1 = (SELECT COUNT(*) FROM #tempProcess_tax_1)
SET #RowCounter_1 = 1
WHILE #RowCounter_1 <= #NumberRecords_1
BEGIN
DECLARE #clid_ INT
DECLARE #hlid_ INT
DECLARE #holdinNo_ NVARCHAR(50)
DECLARE #holding_ NVARCHAR(50)
DECLARE #clientid_ NVARCHAR(100)
DECLARE #clientName_ NVARCHAR(250)
DECLARE #bill AS MONEY
DECLARE #sr AS MONEY;
SELECT
#clid_ = clid_,
#hlid_ = hlid_,
#holdinNo_ = holdinNo_, #holding_ = holding_,
#clientid_ = clientid_, #clientName_ = clientName_
FROM
#tempProcess_tax_1
WHERE
RowID = #RowCounter_1
SET #bill = (SELECT
CASE WHEN SUM(netvalue) IS NULL
THEN 0
ELSE SUM(netvalue)
END
FROM
tx_bill
WHERE
hlid = #hlid_
AND itemID NOT IN (8, 6)
AND YEAR(date_month) = YEAR(#tdate))
SET #sr = (SELECT
CASE WHEN SUM(asset * rate / 100) IS NULL
THEN 0
ELSE SUM(asset * rate / 100)
END
FROM
tx_bill
WHERE
hlid = #hlid_
AND itemID = 6
AND YEAR(date_month) = YEAR(#tdate))
INSERT INTO tx_bill_pay(clid, hlid, swercharge, pay_bill, pdate, bill_id, holdingNo, holding, ClientID, ClientName, billno, date_month, bill, install, inserted_by, inserted_date)
VALUES (#clid_, #hlid_, #sr, #bill / 4, DATEADD(day, -1, DATEADD(m, 3, #tdate)), CONCAT(#holdinNo_, YEAR(#tdate), '1'), #holdinNo_, #holding_, #clientid_, #clientName_, CONCAT(#holdinNo_, YEAR#tdate)), #tdate, #bill, 1, #userid, GETDATE())
INSERT INTO tx_bill_pay(clid, hlid, swercharge, pay_bill, pdate, bill_id, holdingNo, holding, ClientID, ClientName, billno, date_month, bill, install, inserted_by, inserted_date)
VALUES (#clid_, #hlid_, 0, 2 * (#bill / 4), DATEADD(day, -1, DATEADD(m, 6, #tdate)), CONCAT(#holdinNo_, YEAR(#tdate), '2'), #holdinNo_, #holding_, #clientid_, #clientName_, CONCAT(#holdinNo_, YEAR(#tdate)), #tdate, #bill, 2, #userid, GETDATE())
SET #RowCounter_1 = #RowCounter_1 + 1
END
DROP TABLE #tempProcess_tax_1
END
New query (1-2 mins)
ALTER PROCEDURE [dbo].[process_tax]
#userid varchar(10),
#remark nvarchar(500),
#tdate date ,
#roadno nvarchar(10),
#inst int
as
BEGIN
insert into tx_bill_pay(
clid,
hlid,
swercharge,
pay_bill,
pdate,
bill_id,
holdingNo,
holding,
ClientID,
ClientName,
billno,
date_month,
bill,
install ,
inserted_by,
inserted_date)
select
cl.clid,
cl.id,
swercharge=(select case when sum(asset*rate/100) is null then 0 else
sum(asset*rate/100) end from tx_bill where hlid=cl.id and
itemID =6 and year(date_month)=YEAR(#tdate)),
pay_bill=(select case when sum(netvalue) is null then 0 else
sum(netvalue) end from tx_bill where hlid=cl.id and itemID not
in(8,6) and year(date_month)=YEAR(#tdate))/4,
DATEADD(day,-1,
DATEADD(m,3,#tdate)),
CONCAT(cl.holdinNo, year(#tdate),'1'),
cl.holdinNo,
cl.holding,
cl.ClientID,
cl.clientName,
CONCAT(cl.holdinNo,
year(#tdate)),
#tdate,
bill=(select case when sum(netvalue) is null then 0 else sum(netvalue)
end from tx_bill where hlid=cl.id and itemID not in(8,6) and
year(date_month)=YEAR(#tdate))/4,
1,
#userid, getdate()
from
(select *
from tx_holding as cl
where cl.status=1 and cl.roadno=#roadno) AS cl
INNER JOIN (
select DISTINCT hlid from tx_asset where asset is not null
) AS A
ON Cl.id = A.hlid
INNER JOIN (
select DISTINCT id from tbl_client where client_type='Non-Govt.'
) AS C
ON cl.clid=C.id
WHERE NOT EXISTS
( SELECT 1
FROM tx_bill_pay as bp
WHERE year(date_month)=year(#tdate)
and bp.hlid=cl.id
)
insert into tx_bill_pay(clid,hlid
,swercharge,pay_bill,pdate,bill_id,holdingNo,holding,ClientID,
ClientName, billno, date_month, bill, install ,inserted_by,
inserted_date)
select
cl.clid,
cl.id,
0,
pay_bill=2*((select case when sum(netvalue) is null then 0 else sum(netvalue) end from tx_bill where hlid=cl.id and itemID not in(8,6) and year(date_month)=YEAR(#tdate))/4),
DATEADD(day,-1,
DATEADD(m,3,#tdate)),
CONCAT(cl.holdinNo, year(#tdate),'2'),
cl.holdinNo,
cl.holding,
cl.ClientID,
cl.clientName,
CONCAT(cl.holdinNo, year(#tdate)) ,
#tdate,
bill=(select case when sum(netvalue) is null then 0 else sum(netvalue)
end from tx_bill where hlid=cl.id and itemID not in(8,6) and year(date_month)=YEAR(#tdate))/4,
2,
#userid, getdate()
from
(select *
from tx_holding as cl
where cl.status=1 and cl.roadno=#roadno) AS cl
INNER JOIN (
select DISTINCT hlid from tx_asset where asset is not null
) AS A
ON Cl.id = A.hlid
INNER JOIN (
select DISTINCT id from tbl_client where client_type='Non-Govt.'
) AS C
ON cl.clid=C.id
WHERE cl.id not in
( SELECT hlid
FROM tx_bill_pay
WHERE year(date_month)=year(#tdate)
and hlid is not null group by hlid
)

Answer 1

Great Job removing the loop!
I will point out one possible performance problem, specifically year(date_month)=year(#tdate).
Because a column is wrapped in a function, it is non-SARGABLE. This means that date_month values cannot be evaluated directly and therefore, indexes and statistics for this column cannot be used.
To resolve this I suggest the following changes:
At the top of the SP define two more variables:
DECLARE #YearStart AS DATETIME, #NextYearStart DATETIME
SET #YearStart = DATEADD(yy, DATEDIFF(yy, 0, #tdate ), 0 )
SET #NextYearStart = DATEADD( yy, #YearStart, 1 )
Then replace all instances of year(date_month)=year(#tdate) with
#YearStart <= date_month AND date_month < #NextYearStart
This above expression looks for date_month values greater than or equal to midnight (notice that time component is accounted for) of the first day of the year and less than midnight of the next year.
Next, I would look at the query plan and see if SQL Server gives a "Missing Index" recommendation (it should appear just above the plan diagram, if it does suggest an index). Try adding the recommended missing indexes, then check to see if you get a performance improvement. If you don't get an improvement, remove the index - sometimes suggestions don't help.
Updated
Having 3 sub-queries (populating columns swercharge, pay_bill, bill) using tx_bill table with different WHERE conditions will cause at least 3 evaluations of this table per one main query execution.
It may, depending on the size of the table, be more efficient to calculate all 3 sub-queries once and save results to a temp table (or a table variable) as follows:
SELECT hlid,
ISNULL( SUM( CASE WHEN itemID NOT IN (8, 6) THEN netvalue END ), 0 ) AS Bill,
ISNULL( SUM( CASE WHEN itemID = 6 THEN asset * rate / 100 END ), 0 ) AS Sr
INTO #Bills
FROM tx_bill
WHERE #YearStart <= date_month AND date_month < #NextYearStart
AND NOT hlid IS NULL
GROUP BY hlid
In your main queries, join to this table as follows:
LEFT JOIN #SumBills AS SumBills ON SumBills.hlid = cl.hlid
and in SELECT change assignments as per below example:
pay_bill= ISNULL( SumBills.Bill, 0 ) / 4,
Note: I believe you have a bug in bill column, as the value is divided by 4, where it is not in the original cursor.
The last point:
As #GarethD has said in his answer to your previous question, properly formatting your code significantly reduces the time it takes to understand and change the code. I would go one step further and say that code format represents your attitude to and understanding of the problem at hand.

Answer 2

I added non clustered index then my query take 5 sec to run.That's almost solve my problem. #Alex Thanks for your hard work and time. I will check your tips.I Up vote your comment