Optimize Query - How To Make It An Index Seek

Jun 21, 2004

create table t1(a varchar(50) , b varchar(50))

create index i1 on t1(a)
create index i2 on t1(b)

create view v1
as
select * from t1 where isnull(a,b) = 'test'

select * from v1

The above SQL "select * from v1" is doing a table scan.
What do I do to make it perform an index seek ????

TIA

- ForXLDB

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Simple Query Chooses Clustered Index Scan Instead Of Clustered Index Seek

Nov 14, 2006

the query:

SELECT a.AssetGuid, a.Name, a.LocationGuid
FROM Asset a WHERE a.AssociationGuid IN (
SELECT ada.DataAssociationGuid FROM AssociationDataAssociation ada
WHERE ada.AssociationGuid = '568B40AD-5133-4237-9F3C-F8EA9D472662')

takes 30-60 seconds to run on my machine, due to a clustered index scan on our an index on asset [about half a million rows].  For this particular association less than 50 rows are returned. 

expanding the inner select into a list of guids the query runs instantly:

SELECT a.AssetGuid, a.Name, a.LocationGuid
FROM Asset a WHERE a.AssociationGuid IN (
'0F9C1654-9FAC-45FC-9997-5EBDAD21A4B4',
'52C616C0-C4C5-45F4-B691-7FA83462CA34',
'C95A6669-D6D1-460A-BC2F-C0F6756A234D')

It runs instantly because of doing a clustered index seek [on the same index as the previous query] instead of a scan.  The index in question IX_Asset_AssociationGuid is a nonclustered index on Asset.AssociationGuid.

The tables involved:

Asset, represents an asset.  Primary key is AssetGuid, there is an index/FK on Asset.AssociationGuid.  The asset table has 28 columns or so...
Association, kind of like a place, associations exist in a tree where one association can contain any number of child associations.  Each association has a ParentAssociationGuid pointing to its parent.  Only leaf associations contain assets. 
AssociationDataAssociation, a table consisting of two columns, AssociationGuid, DataAssociationGuid.  This is a table used to quickly find leaf associations [DataAssociationGuid] beneath a particular association [AssociationGuid].  In the above case the inner select () returns 3 rows. 

I'd include .sqlplan files or screenshots, but I don't see a way to attach them. 

I understand I can specify to use the index manually [and this also runs instantly], but for such a simple query it is peculiar it is necesscary.  This is the query with the index specified manually:

SELECT a.AssetGuid, a.Name, a.LocationGuid
FROM Asset a WITH (INDEX (IX_Asset_AssociationGuid)) WHERE
a.AssociationGuid IN (
SELECT ada.DataAssociationGuid FROM AssociationDataAssociation ada
WHERE ada.AssociationGuid = '568B40AD-5133-4237-9F3C-F8EA9D472662')

To repeat/clarify my question, why might this not be doing a clustered index seek with the first query?

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Difference Between Index Seek && Index Scan && Index Lookup Operations?

Oct 20, 2006

please explain the differences btween this logical & phisicall operations that we can see therir graphical icons in execution plan tab in Management Studio

thank you in advance

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Index Scan Vs Index Seek

Mar 1, 2004

I have a really strange problem.

I execute this query:

declare @cid int
set @cid = 2003227

select * from sales s, product p where p.product_Id = s.product_Id and customer_id = @cid

select * from sales s, product p where p.product_Id = s.product_Id and customer_id = @cid or @cid = 0

3 Million rows in sales, 120000 in product.

The first does and index seek, the second an index scan.
The execution plan reports that the scan takes 99.87% of the cost, and the seek takes 0.13%

This problem obviously gets worse the bigger the dataset / query /etc.

The reason I query this, is because it never used to take this long to do index scans. Is there something i can change, something i can fix?

Any help would be appreciated.

Josh

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How To Get Index Seek

May 7, 2008

Hi,

Can I use index seek and still keep 'like' 'or' functionality for the following statement?



--prepare test table

create table entity (Id int identity(1,1), FamName varchar(200), LastName varchar(200))
go
create clustered index entity_id on entity (id)
go
create nonclustered index entity_lastName on entity (lastName)
go
insert into entity select famName,FirstName from table

--test index

declare @LastName varchar(10)
set @LastName = 'a'

select FamName
from entity
where @LastName is null or LastName like @LastName --clustered index scan

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Index Seek Vs Scan

Nov 4, 2002

I have created a nolock view off a table to prevent locks. I have users coming in through MS Access that have switched their queries to run against the views. Now we are noticing that queries that used to run as a clustered index seek against the table are running as a clustered index scan against the table and performance in the queries has dropped.

Is there any way that the same query that hits the view instead of the table can be made to run faster or at least use the index seek?

Thanks,

Steve

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Dec 10, 2006

If you display the execution plan and run the following:SET STATISTICS IO ONgoSELECT ProductID, SupplierIDFROM ProductsWHERE SupplierID = 1I don't understand how come there is noBookmark Lookup operation happening to get theProductID?I only see an Index Seek happening on SupplierID.There is no composite index SupplierID + ProductIDso what am I not understanding here?Thank you

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Index Seek, Index Scan, Table Scan

Oct 4, 2007



Hey,

what is the difference between Table Scan und Index Scan?

I find no difitions in the internet

Finchen

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What Is Table Scan, Index Scan And Index Seek??

Sep 21, 2007

Hi,
I want to know wht is a


TABLE SCAN
INDEX SCAN
INDEX SEEKand When they are used, Wht is the difference between all these.????

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SQL 2012 :: Full Text Index How To Make It NOT To Index Embedded Or Attached Documents

Sep 30, 2015

I am using Full Text Index to index emails stored in BLOB column in a table. Index process parses stored emails, and, if there is one or more files attached to the email these documents get indexed too. In result when I'm querying the full text index for a word or phrase I am getting reference to the email containing the word of phrase if interest if the word was used in the email body OR if it was used in any document attached to the email.

How to distinguish in a Full Text query that the result came from an embedded document rather than from "main" document? Or if that's not possible how to disable indexing of embedded documents?

My goal is either to give a user an option if he or she wants to search emails (email bodies only) OR emails AND documents attached to them, or at least clearly indicate in the returned result the real source where the word or phrase has been found.

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Optimize Indexes ...SQL Server Index Tuning Wizard

Jan 8, 2006

I saw this tool for SQL-Server 2000 :
http://www.sql-server-performance.com/index_tuning_wizard_tips.asp

Is there anything similar for SQL-Server 2005 Express ?

Thank you very much for any help!

Regards,
Fabian

my favorit hoster is ASPnix : www.aspnix.com !

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How Do I Make It Use My Index?

Dec 15, 2004

Hello!

I have two tables

users and pictures.

table users have a clustered (PK) index on userid
table pictures have a clustered (PK) index on userid

when I do this query:

"select userid from pictures where userid=123"

then It will do a clustered index seek

But If I do any of those:

"select t2.userid from users t1 left join t2 on t1.userid = t2.userid"
or
"select (select userid from pictures where usedid = t1.userid) from users t1"

It will do a clustered index scan.

How can I force it to seek my index instead of scan?

Thanks!

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HELP ME TO OPTIMIZE QUERY

Feb 2, 2007

Hello friends,
 
I’m facing performance related problem while running following query on SQL Server 2000.
 
This query is basically used to find last location of each unit that are passed. Here I am passing data like “‘26','27','28','29','30','31','32','33','34','35','36','37','38','39','40','41','42','43','44','45','46','47','48','49','50'" in @Units variable. But it takes too much time and I don’t get output. Table is having around 5 Million records.
 
Query:
 
SELECT    Alias, tblUnit.UnitID,  Location, Latitude, Longitude,Convert(varchar(10),UnitHistoryDate,1) + ' ' + substring(Convert(varchar(40),UnitHistoryDate,109),12,9)  + ' ' + substring(Convert(varchar(40),UnitHistoryDate,109),25,2) as [Date/Time], unithistoryid
FROM tblUnit INNER JOIN
tblUnitHistory ON  tblUnit.UnitID =  tblUnitHistory.UnitID
WHERE tblUnitHistory.UnitHistoryDate
IN (SELECT MAX(UnitHistoryDate) FROM tblUnitHistory WHERE  tblUnitHistory.UnitID in (' + @Units + ') GROUP BY tblUnitHistory.UnitID)
AND tblUnit.UnitID in (' + @Units + ')
ORDER BY tblUnit.UnitID
 
 
Table Structure:
 
UnitHistoryID                             int   Primary Key
UnitID                                       int                    
Location                                    varchar(200)     
Latitude                                     decimal            9         
Longitude                                  decimal            9         
Speed                                       decimal 5         
BatteryVoltage                           decimal 5         
ReasonCode                              int
DistanceFromLastLocation            decimal 9         
UnitHistoryDate                         datetime
 
Indexes:
 
1. Clustered Index on Column UnitID
2. Non-clustered Index on Column UnitHistoryDate
3. Non-clustered Index on Column UnitHistoryID
 
Please help me to write optimize query and suggest me the steps to require making this query faster. Any help is appreciated. Thanks in advance.
 
Regards,
Sandeep

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Oct 12, 2007

I have a nightly job that aggregates data into a summary table.  Each night, an additional item may or may not be added, so the table is cleared and repopulated.  I've got this working fine.  Now, I am being asked to track when an item first appears in the summary table.  Here is the code I am using to do this.  I realize it is very poor performance, but I don't know how to make it better.
MyTable Columns:  id INT PK  ,v1 VARCHAR(4)  ,v2 VARCHAR(10  ,v3 DECIMAL  ,item1 BIT  ,item2 BIT  ,item3 BIT
MyTable2 Columns:  v1 VARCHAR(4)  ,v2 VARCHAR(10  ,v3 DECIMAL  ,item INT  ,FirstKnownDate DATETIME
All columns are NOT NULL.1 DECLARE @iNextRowID INT
2 ,@iCurrentRowID INT
3 ,@iLoopControl INT
4 ,@v1 VARCHAR(4)
5 ,@v2 VARCHAR(10)
6 ,@v3 DECIMAL
7
8 /* This is a loop that executes for a dynamic number of items, eg item1=1, then item2=1, etc */
9 SET @iLoopControl=1
10 SELECT @iNextRowID=MIN(id) FROM MyTable WHERE item1=1
11
12 IF ISNULL(@iNextRowID,0) <> 0 BEGIN
13 SELECT @iCurrentRowID = id
14 ,@v1 = v1
15 ,@v2 = v2
16 ,@v3 = v3
17 FROM MyTable
18 WHERE id=@iNextRowID
19
20 WHILE @iLoopControl = 1 BEGIN
21 IF NOT EXISTS(SELECT * FROM MyTable2 WHERE v1=@v2 AND v2=@v2 AND v3=@v3 AND item=1) BEGIN
22 INSERT INTO MyTable2
23 /* COLUMN */ (v1,v2,v3,item,firstknowndate)
24 SELECT @v1, @v2, @v3, 1, GETDATE()
25 END
26
27 SELECT @iNextRowID = NULL
28 SELECT @iNextRowID = MIN(id) FROM MyTable WHERE id>@iCurrentRowID AND item1=1
29
30 IF ISNULL(@iNextRowID,0) = 0 BEGIN
31 BREAK
32 END
33
34 SELECT @iCurrentRowID = id
35 ,@v1 = v1
36 ,@v2 = v2
37 ,@v3 = v3
38 FROM MyTable
39 WHERE id=@iNextRowID
40 END
41 END42 /* This is the end of the items loop */
This query takes 5 minutes to do straight inserts without the test for exists in the loop for 3 items.  MyTable has just under 96,000 rows in it. MyTable2 has 121,857 rows in it. It is not about 55 minutes and it is still running with the exists so that a row isn't inserted twice. Is there anything I can do to optimize this? EDIT: The query just finished running again with the test for exists on each row. It shouldn't have inserted any new rows, but it took 57 minutes and inserted another 114,115 rows. Not good. Anyone see what is wrong with the query?

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Need Help To Optimize Query

May 25, 2005

Hi all,

I need help to optimize this query:

Code:


SELECT s.konto, s.sifra_partnera, s.temeljnica, s.rbr, s.duguje, s.potrazuje, s.saldo
FROM saldakonti s
WHERE
s.datum<'2005-01-01' AND
s.uplata='R' AND
EXISTIS (SELECT t.temeljnica, t.rbr FROM saldakonti t WHERE
t.konto=s.konto AND
t.sifra_partnera=s.sifra_partnera AND
t.vezni_broj=s.vezni_broj and
t.datum<'2005-01-01' AND
(t.uplata='S' or t.uplata='U')
GROUP BY t.temeljnica, t.rbr
HAVING
abs(sum(t.duguje-t.potrazuje))<>abs(s.saldo))
ORDER BY
s.konto, s.sifra_partnera, s.temeljnica, s.rbr, s.duguje, s.potrazuje, s.saldo


Currently this query takes forever to execute. Any suggestions appreciated.
Thanks in advance.

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Feb 26, 2004

Can someone look at this sql statement and tell me if it can be sped up? Also I have to add to it by joining it with another table. How do I do that? Just by nesting another join?

Thanks!


Set rs=Server.CreateObject("ADODB.Recordset")
sql = "SELECT td.TeamID, td.TeamName, rt.PartID, rt.Effort, rt.UnitMeas, pd.MinMilesConv "
sql = sql & "FROM TeamData td INNER JOIN PartData pd ON td.TeamID = pd.TeamID "
sql = sql & "JOIN RunTrng rt ON pd.PartID = rt.PartID "
sql = sql & "WHERE rt.TrngDate >= '" & Session("beg_date") & "' AND rt.TrngDate < '" & Session("end_date")
sql = sql & "' AND pd.Archive = 'N' AND pd.Gender = '" & sGender & "' AND pd.Grade >= " & iMinGrade
sql = sql & " AND pd.Grade <= " & iMaxGrade & " ORDER BY td.TeamID"
rs.Open sql, conn, 1, 2

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Query Optimize.

Mar 25, 2004

Hi all,

Table 'A' is having 105 fields & 233000 records.
One Clusterd Primary Key & 10 nonclusterd key.

If I joined with table 'A' or 'Select * from 'A' , Query takes more time so please let me know best way to structure query or table, Indexes etc.

Reply to me asap positivaly ....

Regards,
M. G.

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Optimize Query.

Apr 1, 2004

Hi All,

please look into below query.



SELECT TOP 101 Cert_WarehouseDetails.CertID, Cert_WarehouseDetails.UnderwriterID,
Cert_WarehouseDetails.WarehouseEntriesID, Cert_WarehouseDetails.DivisionWarehouseLocID,
Cert_WarehouseDetails.TypeID, Cert_WarehouseDetails.ReportingType, Cert_WarehouseDetails.CertWHID,
Cert_WarehouseDetails.ClientPolicyDivisionID, Cert_WarehouseDetails.RecordNO, Cert_WarehouseDetails.InsuredValueX,
Cert_WarehouseDetails.PremiumTotalX, Cert_WarehouseDetails.StatusX, Cert_WarehouseDetails.StatusID,
Cert_WarehouseDetails.AuthorizeDateX, Cert_WarehouseDetails.CodeX, Cert_WarehouseDetails.IssuedDateX, Cert_WarehouseDetails.BillofLadingDateX,
DOGX, Cert_WarehouseDetails.ConveyanceNameX, Cert_WarehouseDetails.LogonNameX , Cert_WarehouseDetails.ClientNameX,
(CASE WHEN UnderwriterID = 0 THEN ' ' ELSE tblClientUsers.FirstName + ' ' + tblClientUsers.LastName END) AS OwnedBy,
(CASE WHEN UnderwriterID = 0 THEN CAST(' ' AS NVARCHAR) ELSE CAST(TakeOwnershipDate as nvarchar) END) AS OwnedDate

FROM
( SELECT tblCertificates.[CertID] AS CertID, tblCertificates.[UnderwriterID] AS UnderwriterID, tblReportingType.[TypeID] AS TypeID, tblReportingType.[ReportingType] AS ReportingType, NULL AS WarehouseEntriesID, NULL AS DivisionWarehouseLocID , tblCertificates.CertID AS CertWHID, tblCertificates.ClientPolicyDivisionsID AS ClientPolicyDivisionID, tblCertificates.CertificateNo AS RecordNO, tblCertificates.TotalInsured AS InsuredValueX, (CASE WHEN tblCertificates.Status=101 or tblCertificates.Status=104 or tblCertificates.DivReferral=1 THEN 0 ELSE PremiumTotal-tblCertificates.Discount END) AS PremiumTotalX, tblStatus.Description AS StatusX, tblStatus.StatusID AS StatusID, (CASE WHEN tblCertificates.Status < '105' and tblCertificates.Status <> '103' THEN null ELSE AuthorizeDate END) AS AuthorizeDateX, tblCurrency.Code AS CodeX, tblCertificates.IssuedDate AS IssuedDateX, tblCertificates.BillofLadingDate AS BillofLadingDateX, tblCertificates.DescriptionofGoods AS DOGX, tblCertificates.ConveyanceName AS ConveyanceNameX, tblClientUsers.LogonName AS LogonNameX , tblClient.ClientName AS ClientNameX, tblCertificates.TakeOwnershipDate AS TakeOwnershipDate, tblCertificates.ClientID AS ClientID, tblCertificates.Producer AS BrokerID, tblCertificates.SBU AS SBU, tblCertificates.AssociationID AS AssociationID, tblCertificates.AssuredName AS AssuredName, tblCertificates.UserID AS UserID, tblCertificates.Demoflag AS Demoflag FROM tblCertificates, tblReportingType,tblcurrency,tblClientUsers,tblCli ent,tblStatus WHERE tblCertificates.reportType = tblReportingType.TypeID AND tblCertificates.PremiumCurrencyType = tblCurrency.ID AND tblclientUsers.UserID = tblCertificates.UserID AND tblcertificates.ClientId = tblclient.ClientID AND tblStatus.StatusID = tblCertificates.Status
UNION
SELECT NULL AS CertID, NULL AS UnderwriterID, tblReportingType.[TypeID] AS TypeID, tblReportingType.[ReportingType] AS ReportingType, tblWarehouseEntries.[WarehouseEntriesID] AS WarehouseEntriesID, tblWarehouseEntries.[DivisionWarehouseLocID] AS DivisionWarehouseLocID , tblWarehouseEntries.WarehouseEntriesID AS CertWHID, tblWarehouseEntries.ClientPolicyDivisionID AS ClientPolicyDivisionID, tblWarehouseEntries.WarehouseEntriesID AS RecordNO, (CASE WHEN ValueCurrencyType=0 THEN 0 ELSE UnitValue END) AS InsuredValueX, (CASE WHEN tblWarehouseEntries.StatusID=101 THEN 0 ELSE PremiumSum END) AS PremiumTotalX, tblStatus.Description AS StatusX, tblStatus.StatusID AS StatusID, (CASE WHEN tblWarehouseEntries.StatusID < '105' THEN null ELSE ApprovalDate END) AS AuthorizeDateX, tblCurrency.Code AS CodeX, tblWarehouseEntries.IssuedDate AS IssuedDateX, tblWarehouseEntries.PeriodEndDate AS BillofLadingDateX, LocName AS DOGX, '' AS ConveyanceNameX, tblClientUsers.LogonName AS LogonNameX , tblClient.ClientName AS ClientNameX, tblWarehouseEntries.TakeOwnershipDate AS TakeOwnershipDate, tblWarehouseEntries.ClientID AS ClientID, tblWarehouseEntries.BrokerID AS BrokerID, tblWarehouseEntries.SBU AS SBU, tblWarehouseEntries.AssociationID AS AssociationID, tblWarehouseEntries.AssuredName AS AssuredName, tblWarehouseEntries.UserID AS UserID, tblWarehouseEntries.Demoflag AS Demoflag FROM tblWarehouseLoc, tblWarehouseEntries, tblReportingType,tblCurrency ,tblClientUsers,tblClient, tblDivisionWarehouseLoc,tblStatus WHERE tblWarehouseEntries.reportTypeID = tblReportingType.TypeID and tblWarehouseLoc.WarehouseLocationID = tblDivisionWarehouseLoc.WarehouseLocID and tblDivisionWarehouseLoc.DivisionWarehouseLocID = tblWarehouseEntries.DivisionWarehouseLocID and tblWarehouseEntries.PremiumCurrencyType = tblCurrency.ID and tblWarehouseEntries.UserID = tblClientUsers.UserID and tblClient.ClientID = tblWarehouseEntries.ClientID AND tblStatus.StatusID = tblWarehouseEntries.StatusID

) AS Cert_WarehouseDetails LEFT JOIN tblClientUsers ON Cert_WarehouseDetails.UnderwriterID = tblClientUsers.UserID

WHERE 1 = 1 AND Cert_WarehouseDetails.Demoflag = 0 and
(convert(datetime,convert(nvarchar,Cert_WarehouseD etails.IssuedDateX,101)) >= '1/1/2003') and
(Cert_WarehouseDetails.IssuedDateX is not null and
convert(datetime,convert(nvarchar,Cert_WarehouseDe tails.IssuedDateX,101)) <= '3/31/2004')
ORDER BY Cert_WarehouseDetails.RecordNO



In above query,as
1. Union (INNER) query returns me 200000 records.

2. If I run above query it takes 18 sec because no index on Cert_WarehouseDetails.RecordNO and i'm ordering on that.

3. When I avoid to 'ORDER BY Cert_WarehouseDetails.RecordNO' then query takes 2 sec.

4. In this case Do I have to use 'nvarchar'
convert(datetime,convert(nvarchar,Cert_WarehouseDe tails.IssuedDateX,101)) <= '3/31/2004')

5. Why do we have to use 'nvarchar' can you explain to me in above statement..


Can you provide me alternate solution so I can make it fast.

Please reply to me asap. Thanks in advance.

Regards,
M. Jain

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Jan 24, 2008

Hi,

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May 18, 2006

Hi,I have these two tables in a DatabaseITEMSIDnumeric (Primary key)ZDIDnvarchar 3 (not null)IDF_Familynumeric(not null)Descriptionnvarchar40 (not null)DATASIDnumeric(Primary Key)IDF_Itemnumeric(Foreign key)IDF_Referencenumeric(Foreign Key)[Date]smalldatetime(not null)Containernchar10(not null)Averagedecimal(not null)[%Compliance]decimal(not null)[%OutOfRange<MinTg]decimal(not null)[%OutOfRange>MaxTg]decimal(not null)Targetdecimal(not null)[Min]decimal(not null)[Max]decimal(not null)The table DATAS has 4000000+ recordsI'm running this query:SELECT DISTINCT I.ID, I.ZDID, I.IDF_Family, I.DescriptionFROM Items as I, Datas as DWHERE D.IDF_Item = I.ID AND I.IDF_Family = 84AND D.Date BETWEEN '5/18/2004' AND '5/18/2004'it's taking 4-5 minutes to run.The result is correct, there is no thing on that date.I've done a reindex, but still the same thing.What can I do?Thanks

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Optimize Query

Nov 17, 2006

Hello,I am trying to find all records that have matching detail_1 or detail_2columns. This is what I have now:select t1.id, t1.detail_1, t1.detail_2, t2.id from user_details t1,user_details t2where t1.detail_1 = t2.detail_1 or t1.detail_2 = t2.detail_2;Using smaller tables of around 1000 records, I have verified that thisindeed does the job. However, when I apply it to the real table thathas around 40,000 records, it takes so long that I have to stop thequery.The table in question is quite simple and is created as follows. Thereare no indexes on the table:create table user_details (id integer, detail_1 varchar(50), detail_2varchar(50)Is there a way to make it go faster?

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Mar 3, 2008

Hi! I have an optimisation problem. I've currently got a query that retrieve about 10K records according the mode that user difined earlier.

At the very beginning I've wrote the same code through the user-defined functions, but I found in publications that it's a wrong way to develop with MSSQL, but it worked more and more faster (3 sec). Now I rewrite my query with inline table functions...CREATE FUNCTION ans_app_name1()


RETURNS TABLE AS RETURN
(SELECT CASE WHEN OBJECT_ID('app_name') > 0 THEN
(SELECT TOP(1) app_name FROM app_name WHERE spid = @@spid)
ELSE NULL END AS app_name )
GO

CREATE FUNCTION ans_get_user_property1(
@property_name VARCHAR(255))
RETURNS TABLE AS RETURN
(SELECT u.value AS user_property FROM user_property u
JOIN ans_app_name1() a ON a.app_name = u.app_name
WHERE property = @property_name AND
username = system_user)
GO

CREATE FUNCTION ans_get_mode()
RETURNS TABLE AS RETURN
(SELECT CAST(user_property AS INT) AS mode FROM ans_get_user_property1('mode'))
GO

CREATE FUNCTION ans_get_state_date()
RETURNS TABLE AS RETURN
SELECT
CASE
WHEN ((SELECT mode FROM ans_get_mode()) IN (3,6)) THEN
CAST(user_property AS DATETIME) END AS state_date
FROM ans_get_user_property1('state_date')
GO

ALTER FUNCTION is_real1(
@mode INT,
@state_date DATETIME)
RETURNS TABLE AS
RETURN (
SELECT uid,
CASE

WHEN (begin_date = 0) or (end_date = 0) THEN 0

WHEN
((@mode IN (1,5)) AND (begin_date <= CURRENT_TIMESTAMP) AND ((end_date IS NULL) OR (end_date > CURRENT_TIMESTAMP)))

OR ((@mode IN (2,5,6)) AND (begin_date IS NULL) AND (end_date IS NULL) AND ISNULL(is_committed, 0) = 0)

OR ((@mode IN (3,6)) AND (begin_date <= @state_date) AND ((end_date IS NULL) OR (end_date > @state_date)))

OR ((@mode = 4) AND (begin_date <= CURRENT_TIMESTAMP) AND ((end_date IS NULL) OR (end_date > CURRENT_TIMESTAMP)))
THEN 1
ELSE 0
END AS is_real
FROM host
)
GO

ALTER view v_host as
SELECT
h.uid,
h.id_histland,
h.id_group,
h.numporyadok,
h.numgroup,
h.objidentnum,
h.egrokn_reg_num,
h.kad_num,
h.ansname,
h.objname,
h.id_objprotstatus,
h.id_kategory,
h.id_objkind,
h.id_histcultvalue,
h.uid_objautor,
h.createdate,
h.id_scientifictype,
h.obj_description,
h.id_admdistrict,
h.cityblock,
h.id_settlement,
h.id_admdistrict2,
h.p_index,
h.id_street,
h.housenum,
h.housenumpart,
h.houseliteranum,
h.buildingnum,
h.corneradress,
h.appartmentnum,
h.id_urbanblock,
h.id_microdistrict,
h.kadblock,
h.end_date,
h.objlocation,
h.parent_uid,
h.kaddistrict,
h.mundistrict,
h.is_committed,
h.order_uid,
h.begin_date,
h.cr_date,
h.order_uid_end,
h.uid_parent_host,
h.is_host_object,
h.id_funcassign,
h.id_immovobjtype,
h.hist_data,
CASE WHEN h.obj_code is NULL THEN
'<object registered>'
ELSE h.obj_code
END AS obj_code,
s.sname AS sname_objprotstatus,
k.sname AS sname_kategory,
ok.sname AS sname_objkind,
p.sname AS name_property,
ISNULL(h.ansname + ' ', '') + h.objname as fullname,
h.pre_material,
h.hist_view_change,
h.adr_id,
h.street_id,
h.cod_mun,
h.hist_object_id,
h.scientifictype
FROM
host h
LEFT JOIN sl_objprotstatus s ON h.id_objprotstatus = s.id
LEFT JOIN sl_kategory k ON h.id_kategory = k.id
LEFT JOIN sl_objkind ok ON h.id_objkind = ok.id
LEFT JOIN sl_property p ON h.id_property = p.id
--JOIN is_real1((SELECT mode FROM ans_get_mode()), (SELECT state_date FROM ans_get_state_date())) r ON r.uid = h.uid
WHERE
(CASE

WHEN (begin_date = 0) or (end_date = 0) THEN 0

WHEN
(((SELECT mode FROM ans_get_mode()) IN (1,5)) AND (begin_date <= CURRENT_TIMESTAMP) AND ((end_date IS NULL) OR (end_date > CURRENT_TIMESTAMP)))

OR (((SELECT mode FROM ans_get_mode()) IN (2,5,6)) AND (begin_date IS NULL) AND (end_date IS NULL) AND ISNULL(is_committed, 0) = 0)

OR (((SELECT mode FROM ans_get_mode()) IN (3,6)) AND (begin_date <= (SELECT state_date FROM ans_get_state_date())) AND ((end_date IS NULL) OR (end_date > (SELECT state_date FROM ans_get_state_date()))))

OR (((SELECT mode FROM ans_get_mode()) = 4) AND (begin_date <= CURRENT_TIMESTAMP) AND ((end_date IS NULL) OR (end_date > CURRENT_TIMESTAMP)))
THEN 1
ELSE 0
END) = 1
GO


set statistics time on

-- cleaning cache
dbcc dropcleanbuffers
dbcc freeproccache

SELECT * FROM v_host
/*
(9777 row(s) affected)

SQL Server Execution Times:
CPU time = 9718 ms, elapsed time = 10834 ms.
*/

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Please Help Optimize My Query?

May 1, 2007

Hello all!

I've currently got a query that takes two tables with the same structure, and spits out the differences in the second table - this is done to help me see what new records have been added in the second table that don't exist in the first. The only catch is that I have to compare two columns in sort of a pseudo-composite-key. Here's the gist of the table structure:

Table A:
ID (Autonumber),
Firstname,
Lastname,
OS,
PC Manufacturer

Table B (The new one):
Firstname,
Lastname,
OS,
PC Manufacturer

The two columns I have to compare are firstname and lastname, as there aren't any other unique identifiers that match between the two tables. Right now, I'm using some really convoluted WHERE statements, and I suspect that it could be done more cleanly. Does anyone have any suggestions?

Thanks in advance...

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Optimize Query

Jan 16, 2008



Below you see a query I run.

The result of this query is shown below...
The result shows fields such as Bid_Price_Best_Latest and Ask_Price_Best_Latest may or may not have null values.
At present, I use a cursor to get the values of these two fields if any of them is null from the table tblPricesSourcesImportHistory for the latest Import_Date on each record.
These two fields are referred to as Bid_Price, Ask_Price in tblPricesSourcesImportHistory.

Now I would like to find out how to do this without the use of a cursor, so that I can speed up this query.

Thanks


select
fp.Security_ID,
fp.Security_Name,
fp.Bid_Price_Best_Latest,
fp.Bid_Size_Best_Latest,
fp.Bid_Source,
fp.Ask_Price_Best_Latest,
fp.Ask_Size_Best_Latest,
fp.Ask_Source
from
tblTEST fp
left join tblSources s on fp.Security_ID = s.Security_ID
inner join tblPricesSourcesImportHistory h on
h.Source_ID = s.Source_ID
where
(fp.Bid_Price_Best_Latest is null) or (fp.Ask_Price_Best_Latest is null)
group by
fp.Security_ID,
fp.Security_Name,
fp.Bid_Price_Best_Latest,
fp.Bid_Size_Best_Latest,
fp.Bid_Source,
fp.Ask_Price_Best_Latest,
fp.Ask_Size_Best_Latest,
fp.Ask_Source
order by
fp.Security_ID

fp.Security_ID Security_Name Bid_Price_Best_Latest Bid_Size_Best_Lates Bid_Source Ask_Price_Best_Latest Ask_Size_Best_Latest Ask_Source
1 Alli 84.0000 0.50 G NULL NULL NULL
2 bow 82.5000 0.50 G NULL NULL NULL
4 xte NULL NULL NULL 90.0000 0.50 G
6 Wqu 84.5000 0.50 I NULL NULL NULL
...
...
...

Not sure if it helps but here are the structures of the tables you may need...

CREATE TABLE [dbo].[tblSources](
[Source_ID] [int] IDENTITY(1,1) NOT NULL,
[Security_ID] [smallint] NOT NULL,
[Source_Parent] [varchar](50) NOT NULL,
[Source_Code] [varchar](20) NOT NULL,
[Source_Security_Name] [varchar](50) NOT NULL)



CREATE TABLE [dbo].[tblPricesSourcesImportHistory](
[Price_Source_Import_History_ID] [int] IDENTITY(1,1) NOT NULL,
[Source_ID] [smallint] NULL,
[Source_Parent] [varchar](255) NULL,
[Source_Code] [varchar](255) NULL,
[Security_Name] [varchar](255) NULL,
[Source_Security_Name] [varchar](255) NULL,
[Bid_Price] [varchar](255) NULL,
[Bid_Size] [varchar](255) NULL,
[Ask_Price] [varchar](255) NULL,
[Ask_Size] [varchar](255) NULL,
[Import_Date] [smalldatetime] NOT NULL)

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Optimize & Trim Query

Nov 21, 2001

I’m trying to optimize the following view so that it runs faster and to trim the code where possible. It runs for 1:57mins. Is that good or it can run much faster than that? Where do l start? It’s a view for a report. Please help l’m running on SQL 2000

CREATE View SalesTest AS
SELECT dbo.Loan.loan_No AS [Loan No], dbo.Customer.customer_No AS [Customer No], dbo.Customer.first_Name + ' ' + dbo.Customer.surname AS Customer,
dbo.Employer.employer_Name AS [Employer Name], dbo.Loan.store AS [Store No], dbo.Store.store_Name AS Store,
dbo.Region.region_Description AS Region, dbo.Financier.financier_Short + dbo.Term.term_Description AS Product,
dbo.Loan.date_Issued AS [Transaction Date], dbo.Loan.capital_Amount AS [Capital Amount], dbo.Loan.interest_Amount AS [Interest Amount],
dbo.Loan.interim_Interest_Amount AS [Interim Interest Amount], dbo.Loan.interest_Amount + dbo.Loan.interim_Interest_Amount AS [Interest2 Amount],
dbo.Loan.insurance_Amount AS [Insurance Amount], dbo.Loan.admin_Fee AS [Admin Fee], dbo.Loan.total_Amount AS [Total Amount],
dbo.Loan_Type.loan_Type_Description AS [Loan Type Description], dbo.Loan.user_Changed AS [User], dbo.Loan.first_Payment AS [First Payment],
dbo.Loan.monthly_Payment AS [Monthly Payment], dbo.Loan.repayment_Period AS [Repayment Period],
dbo.Loan.outstanding_Amount AS [Outstanding Amount], dbo.Loan.last_Payment_Date AS [Last Payment Date],
dbo.Status.status_Description AS Status, CONVERT(Char(3), dbo.Loan.loan_No, 1) AS Company, dbo.Customer.physical_Address1 AS Mine1,
dbo.Customer.physical_Address2 AS Mine2, dbo.Customer.physical_Address3 AS Mine3, dbo.Loan.maturity_Date AS [Maturity Date],
dbo.Agent.agent_Short AS Agent, dbo.Financier.financier_Short AS Financier, dbo.Loan.product AS [Loan Product],
dbo.Deduction_Detail.teba_Account_No AS [Teba Account No]
FROM dbo.Loan INNER JOIN
dbo.Customer ON dbo.Customer.customer_No = dbo.Loan.customer_No INNER JOIN
dbo.Status ON dbo.Status.status = dbo.Loan.status INNER JOIN
dbo.Store ON dbo.Store.store = dbo.Loan.store INNER JOIN
dbo.Product ON dbo.Product.product = dbo.Loan.product INNER JOIN
dbo.Product_Type ON dbo.Product_Type.product_Type = dbo.Product.product_Type INNER JOIN
dbo.Financier ON dbo.Financier.financier = dbo.Product_Type.financier INNER JOIN
dbo.Term ON dbo.Term.term = dbo.Product.term INNER JOIN
dbo.Employer ON dbo.Employer.employer = dbo.Customer.employer INNER JOIN
dbo.Region ON dbo.Region.region = dbo.Store.region INNER JOIN
dbo.Loan_Type ON dbo.Loan_Type.loan_Type = dbo.Product_Type.loan_Type INNER JOIN
dbo.Agent ON dbo.Agent.agent = dbo.Product_Type.agent INNER JOIN
dbo.Deduction_Detail ON dbo.Loan.customer_No = dbo.Deduction_Detail.customer_No AND
dbo.Loan.deduction_No = dbo.Deduction_Detail.deduction_No
WHERE (dbo.Loan.outstanding_Amount <> 0)

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How To Optimize This Slow Query?

Mar 25, 2004

tblElements.ID is a foreign key to tblOwner.eID
@PrevRec = dynamic number of previous records
@owner = owner ID

SELECT TOP 2 tblOwner.eID FROM tblOwner
LEFT JOIN tblElements ON
tblElements.ID = tblOwner.eID
WHERE tblOwner.own_ID = @Owner AND tblElements.ID NOT IN
(SELECT TOP + @PrevRec + tblOwner.eID FROM tblOwner
LEFT JOIN tblElements ON
tblElements.ID = tblOwner.eID WHERE tblOwner.own_ID = @Owner) ORDER BY tblOwner.eID ASC

This query is used to display one record per page on a ASP paging script, I select top 2 because, I want to be able to know if I have another page or record to go to and deside if I need to display the "Next" button.

Also It is suppose to select records only assigned to it's ower.
It works fairly quick when viewing first few hundred records, then it takes a very long time.

I have indexed ID and eID as clustered indexes also tblOwner could have multiple instances eID.

Is there an easier way of writing this out.

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How To Optimize Following Query For Execution Time

Mar 18, 2008

Hell All,
Following query takes 7 minutes to execute while using search criteria as shown below in blue text(ie. IN(2006,2007)
if criteria changes to =2006 as shown in 2),this takes 2minutes

But I want expected output as in query 1) in less time.
How to optimize following query for execution time?

1)select sum(PB.CONSN_QTY)Consumption,Count(*),PB.BillPro_Year
from tbtrans_prowaterbill PB
INNER JOIN MIDC_AREA MA
ON PB.Area_cd = MA.Area_cd INNER JOIN MIDC_Division MD ON MA.Div_CD = MD.Division_CD
INNER JOIN MIDC_Circle MC ON MD.Circle_CD = MC.Circle_CD
INNER JOIN TBMST_SubDiv TS ON MA.SubDiv_CD = TS.SubDiv_CD
INNER JOIN MIDC_Zone MZ ON MD.Zone_CD = MZ.Zone_CD
INNER JOIN tbmst_consumer TC ON PB.cons_no = TC.Cons_No
INNER JOIN TBMST_CONSTYPE TCT ON TCT.Cons_Type = TC.Cons_Type
where pb.billpro_year IN('2006','2007') and MTR_Size = 15 and TCT.Cons_Type = '1A2'
and MZ.Zone_Name = 'MUMBAI' and MC.Circle_NAME = 'MMR' and MD.Division_Name = 'Dombivli' and TS.SubDiv_DESC = 'THANE DIVISION STAFF'
group by PB.BillPro_Year





2)select sum(PB.CONSN_QTY)Consumption,Count(*),PB.BillPro_Year
from tbtrans_prowaterbill PB
INNER JOIN MIDC_AREA MA
ON PB.Area_cd = MA.Area_cd INNER JOIN MIDC_Division MD ON MA.Div_CD = MD.Division_CD
INNER JOIN MIDC_Circle MC ON MD.Circle_CD = MC.Circle_CD
INNER JOIN TBMST_SubDiv TS ON MA.SubDiv_CD = TS.SubDiv_CD
INNER JOIN MIDC_Zone MZ ON MD.Zone_CD = MZ.Zone_CD
INNER JOIN tbmst_consumer TC ON PB.cons_no = TC.Cons_No
INNER JOIN TBMST_CONSTYPE TCT ON TCT.Cons_Type = TC.Cons_Type
where pb.billpro_year = '2006' and MTR_Size = 15 and TCT.Cons_Type = '1A2'
and MZ.Zone_Name = 'MUMBAI' and MC.Circle_NAME = 'MMR' and MD.Division_Name = 'Dombivli' and TS.SubDiv_DESC = 'THANE DIVISION STAFF'
group by PB.BillPro_Year

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Help Me Optimize A Daily Events Query

Nov 1, 2006

We keep a database of events that are classified by severity. I've got a good, efficient query that gives me the grand total for these events. And I have a bad slow query that breaks down the information into daily totals.

My fast query will count the totals for 3213586 events in 4 seconds. The slow daily query takes about 60 seconds for each day.

Please help optimize my slow query!

------ Database schema is:












Column Name
Data Type
Length
Allow Nuls

1
msrepl_tran_version
uniqueidentifier
16
0

0
[time]
GMTtime (int)
4
0

0
msec
int
4
1

0
offset
GMToffset (smallint)
2
0

0
type
nameType (varchar)
15
1

0
host
nameType (varchar)
15
1

0
process
nameType (varchar)
15
1

0
dbName
nameType (varchar)
15
1

0
ptName
nameType (varchar)
15
1

0
description
descType (varchar)
47
1

0
rtuName
nameType (varchar)
15
1

0
groupName
nameType (varchar)
15
1

0
message
msgType (varchar)
131
0

0
fgInt
tinyint
1
1

0
sevInt
tinyint
1
1

0
key1
int
4
1

0
key2
int
4
1

0
spooler
tinyint
1
1

------- The database view eventView that's used by my queries:
SELECT DATEADD([second], [time] + 60 * offset, '01/01/70') AS timeStr, msec, host, process, dbName, ptName AS point, description, rtuName AS rtu, groupName, message, type, sevInt, [time]
FROM dbo.summary

------- Fast totals query:

select
(select count(*)
from [event].[dbo].[eventView]) as Events,
(select count(*)
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 1)as Low,
(select count(*)
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 2)as Medium,
(select count(*)
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 3) as High,
(select count(*)
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 4) as Low1,
(select count(*)
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 6) as Medium1,
(select count(*)
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 8) as High1,
(select count(*)
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 9) as High2

------- Slow daily query:

declare @myDay datetime
declare @begDay datetime

declare @myTable
table( myDay datetime,
Events int,
Low int, Medium int,
High int, Low1 int, Medium1 int,
High1 int, High2 int )

select @myDay = getdate()

select @begDay = convert(datetime, '10/01/2006')

while @begDay <= @myDay
begin

insert into @myTable (myDay) values (convert(varchar(20), @begDay, 101))

---------------------------------------------------------------------

update @myTable set Events =
(select count(*) as Events
from [event].[dbo].[eventView]
where
convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

update @myTable set Low =
(select count(*) as Low
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 1
and convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

update @myTable set Medium =
(select count(*) as Medium
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 2
and convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

update @myTable set High =
(select count(*) as High
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 3
and convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

update @myTable set Low1 =
(select count(*) as Low1
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 4
and convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

update @myTable set Medium1 =
(select count(*) as Medium1
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 6
and convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

update @myTable set High1 =
(select count(*) as High1
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 8
and convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

update @myTable set High2 =
(select count(*) as High2
from [event].[dbo].[eventView]
where type = 'alarm' and sevInt = 9
and convert(varchar, timeStr, 101) = convert(varchar(20), @begDay, 101))
where myDay = convert(varchar(20), @begDay, 101)

---------------------------------------------------------------------

select @begDay = dateadd(day,1,@begDay)

end

select * from @myTable

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Any Suggestions On How To Optimize A Query Written In Dynamic SQL?

Oct 15, 2007

I added the subquery and now this thing consistently takes more than five minutes to return 7100+ rows. Any suggestions? Thanks again, you guys are the best.

ddave
----------------------------
SET @StrQry1 = '(SELECT 1 AS Counter, Q1.SubsidyLevel, VEL.*
FROM dbo.ViewEligibilityPHC VEL
LEFT OUTER JOIN (SELECT *
FROM dbo.MEMB_LISHISTS l
WHERE l.LISThruDate is null
AND l.Deleted = ''0'') AS Q1 ON VEL.MEMBID = Q1.MemberID
WHERE VEL.OPTHRUDT is null
AND VEL.OPT LIKE ''' + @HPlan + ''' AND (VEL.PCP IS NULL OR VEL.PCP LIKE ''' + @Prvdr + ''')
AND VEL.HCC LIKE ''' + @HCC + ''' AND (VEL.CaseMgrID IS NULL OR VEL.CaseMgrID LIKE ''' + @CaseMngr + ''')
AND VEL.OPFROMDT <= CAST(''' + @SDate + ''' AS datetime)
AND ISNULL(VEL.OPTHRUDT, CAST(''' + @TDate + ''' AS datetime)) >= CAST(''' + @EDate + ''' AS datetime)) '

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Many Or Operation Make System Choose Incorrect Index

Nov 26, 2007

Hi All,I have one question about many "or" operation make system chooseincorrect indexThere is one table TT (C1 VARCHAR(15) NOT NULL,C2 VARCHAR(15) NOT NULL,C3 VARCHAR(15) NOT NULL,C4 VARCHAR(15) NOT NULLC5 VARCHAR2(200),)Primary Key TT_PK (C1, C2, C3, C4)SELECT C1, C2, C3, C4 FROM TT WHERE C1 = 'TEST' AND ((C2 ='07RES' AND C3 = '00000' AND C4 = '02383') OR (C2 = '07RES' ANDC3 = '00000' AND C4 = '02382') OR (C2 = '07RES' AND C3 = '00000'AND C4 = '02381') OR (C2 = '07RES' AND C3 = '00000' AND C4 ='02380') OR (C2 = '07RES' AND C3 = '00000' AND C4 = '02379') OR(C2 = '07RES' AND C3 = '00000' AND C4 = '02378') OR (C2 = '07RES'AND C3 = '00000' AND C4 = '02377') OR (C2 = '07RES' AND C3 ='00000' AND C4 = '02376') OR (C2 = '07RES' AND C3 = '00000' ANDC4 = '02375') OR (C2 = '07RES' AND C3 = '00000' AND C4 ='02374') OR (C2 = '07RES' AND C3 = '00000' AND C4 = '02373') OR(C2 = '07RES' AND C3 = '00000' AND C4 = '02372').... about 100 or operationsOR (C2 = '07COM' AND C3 = '00000' AND C4 = '00618') OR (C2 ='07COM' AND C3 = '00000' AND C4 = '00617') OR (C2 = '07COM' ANDC3 = '00000' AND C4 = '00616') OR (C2 = '07COM' AND C3 = '00000'AND C4 = '00608') )The system choose index prefix, and query all index leaf withC1='TEST'Prefix: [dbo].[TT].C1 = 'TEST'After I reduce the OR operators to 50, it use choosePrefix: [dbo].[TT].C1, [dbo].[TT].C2,[dbo].[TT].C3,[dbo].[TT].C4='TEST, '07RES', '00000', '02383'Then Merge Join, it is very quick,Can anyone help on this, do I have to reduce the OR operator to 50?Thanks in advance!

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ASC/DESC Clustered Index - Will It Make A Difference In This Scenario?

Sep 7, 2007

Imagine the following scenario-

Identity(1,1) column ID is primary key and only clustered index key.

Rows will be inserted regularly into this table, hundreds per day.

Queries will be mostly selecting on the most recent records.

In a year, the row will have half a million records or so and only the most recent records will be used. There will be a forward-rolling hot spot, of most recent records.

Does the direction of the ID column in the clustered index make a difference?

I'm thinking no, because query plan will go to that leaf in an index seek regardless of whether it is old or new, "bottom" or "top" of index, especially if the query is very specific on the ID.

I've read this

http://mattadamson.blogspot.com/2005/05/choosing-between-ascending-or.html

but it didn't address (or perhaps didn't need to) this sort of scenario.

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Optimize A UNION Query With LIKE (was Query Help)

Jan 30, 2005

Hi,

SQL 2K
Table loaded using BULK INSERT with ~5 000 000 records.
CREATE TABLE [MyTable] (
[SeqNumber] int NOT NULL ,-- sequence unique number
[ObjId] int NOT NULL ,
[HierarchyLevel] varchar(255) NULL ,-- highest level = 0
[NameText] varchar(255) NULL
.
.
)

insert into MyTable
select 1, 1, 0, 'text-10'
union all select 2, 1, 1, 'text-11 state-1'
union all select 3, 1, 2, 'text-12 social-1'
union all select 4, 1, 3, 'text-13 abc social-1.1'
union all select 5, 1, 1, 'text-11 123'
union all select 6, 1, 1, 'text-11 ABCDEF'
union all select 7, 1, 2, 'text-12 bbb'
union all select 8, 1, 3, 'text-13 social-2'
union all select 9, 1, 4, 'text-14 aaa'
union all select 10, 2, 1, 'text-21 state-3'
union all select 11, 3, 5, 'text-31 state-2 social-3'

- Unique Index on SeqNumber

Query:
Select top 100 TI.*
from [dbo].[MyTable] TI
inner join [dbo].[MyTable] TL
on TL.ObjId = TI.ObjId
where (TL.[NameText] like '%state%')
and TI.[NameText] like '%social%'
and TI.HierarchyLevel > TL.HierarchyLevel
and TI.SeqNumber > TL.SeqNumber
and not exists (select *
from [dbo].[MyTable] T3
where T3.ObjId = TL.ObjId
and T3.SeqNumber > TL.SeqNumber
and T3.SeqNumber < TI.SeqNumber
and T3.HierarchyLevel <= TL.HierarchyLevel)
Union
Select T4.*
from [dbo].[MyTable] T4
where T4.[NameText] like '%state%'
and T4.[NameText] like '%social%'
order by Ti.SeqNumber

Result:
SeqNumber ObjId HierarchyLevel NameText
312text-12 social-1
413text-13 abc social-1.1
1135text-31 state-2 social-3

Could somebody help me please to optimize this query?

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Jan 17, 2007

Hi i am using MS SQL 2000 db ,while executing following prepared statement query its working fine ...BUT when i remove "top 300" then tomcat giving OUT OF MEMORY ERROR!!

i think that its because of the cross join....So i want to optimize this query in such a way that it will not give "Out of memory error"
How can i re write this query?

Query :-

"select top 300 haw.DeviceID as deviceid,haw.Description as Description,haw.SerialNo as SerialNo,haw.Suffix as Suffix,haw.HWRev as HWRev,haw.Type as Type,dev.Status as Status from Hardware_PlaceHolder haw,Device_PlaceHolder dev ,Accounts ac where dev.siteId = ac.siteId and ac.CustID = ? ";

thanks in advance..

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