I had a pretty simple query like
select * from table_A
where email in (select email from table_B)
or
email not in (select email from table_c)
It ran for a very long time.
But if I ran the select with either of the conditions by itself it took just a second. Combining both conditions really slowed it down.
I have someone telling me that I should have put my AND statement in the join instead of the where part, so is there a difference in the where I put it. Is there a difference in the results in any way between the two here in the results in anyway?
Example:
Given a query:
But let’s take a simple one here:
Query(1)
Select ct1.Name, ct1.address, ct1.city, ct1.state, ct1.zipcode
From cutTableA ct1 Left join cutTableA ct2
On ct1.ID = ct2.ID
Where ct1.zipcode = '14124'
AND ct1.Name = 'Bob'
Query(2)
Select ct1.Name, ct1.address, ct1.city, ct1.state, ct1.zipcode
From cutTableA ct1 Left join cutTableA ct2
On ct1.ID = ct2.ID
AND ct1.zipcode = '14124'
Where ct1.Name = 'Bob'
I want to add an exception to the WHERE clause below.
Something like:
IF @IDHuis = 'WH' THEN
add the extra condtion:
AND D.AfdelingZPT <> 'A01'
-- HRS VAST
INSERT INTO @T (JAAR, WEEK, HrsVast)
[Code] .....
I've come across a piece of code which i have never seen before.
ON T.CT_YEAR in
(
case
.[DBO].[FN_GET_YEAR]
(
CAST
(
C.[YEAR] AS VARCHAR(4)
[Code] ....
The CT_Year column is simply C for current year L for last year, O for Other, N for Next.
The Function simply returns the year value.
When I use the following SQL with the variable @CutOFFTID the second select statement query takes several minutes. If i run it replacing the value in the where clause with the acutal value of the variable it runs instantly.
DECLARE @CutOffTid int
SELECT @CutOffTid = isnull(max(ccas_id),0)
FROMdbo.fbs_trans (NOLOCK)
print 'Cut Off ID is ' + cast(@CutOffTid as char)
DECLARE @MinPeriod int
SELECT @MinPeriod = Min(period)
FROM agr.dbo.atrans
WHERE agrtid >@CutOffTid
I need to write a SQL script where a join condition is using date columns (effective_date, ineffective_date). The effective date columns can be slightly different (e.g. differ by a day) for some rows of data. I need the join condition to accommodate these date differences and return these rows of data as well.
I have a table which uses multiple joins to create another table but it turns out that the effective_date which is used in the join to match row together does not work all the time since some of the dates for the effective date column are out of sync meaning records that show data as missing even when the other table contains the data. I tried the SQL script below using the BETWEEN clause but it returning 6 rows instead of 3–
select t2.[entity_id]
,t2.[effective_date]
,[company_name]
,[last_accounts_date]
,[s_code]
,[s_code_description]
[Code] .....
create table deltavalues (planid varchar(10), baseval float, highval float)
Insert into deltavalues values ('1002', 2000,5000)
Insert into deltavalues values ('1003', 1000,0)
Insert into deltavalues values ('1004', 500,0)
Insert into deltavalues values ('1005', 1000,2000)
--I have below query , basically getting emnployee table balance between deltavalues table baseval column and highval column
select * from employee e join deltavalues d on e.planid = d.planid
where e.balance between d.baseval and d.highval
but here what i am requesting you is how can i change the highvalue to not include if it is 0
for example above example plan 1003, 1004 has highbal as 0 so i want to write a query to get employee data between 1000 and anyvalue (> 1000 - no limit)
same way for 1004 between 500 and no end values (infinity)
I am supposed to delete all rows from USER and its child tables based on PracticeID = '55' filter condition.
I have dynamically generated queries to delete child table first followed by parent. Table [EncounterSignOff] si child and [User] is parent.
I would like to know, whether the Query 1 is valid for deleting child records?
Query:1
DELETE Top(100000) FROM [dbo].[EncounterSignOff]
FROM [dbo].[User] INNER JOIN [dbo].[EncounterSignOff] ON [User].[UserID] = [EncounterSignOff].[UserId]
WHERE [User].PracticeID = '55';
Query:2
DELETE Top(100000) FROM [dbo].[User] WHERE [User].PracticeID = '55';
I have a population split between two vendors. One gets last names between A and R, the other the rest. Now, on a given date vendor 1 gets everybody.
I can accomplish this with a case statement on the upper range (R or Z), but it seems I should be able to do this without testing at all after the turnover date.
A small bit of the code:
declare @get_date datetime = convert(char(10),getdate(),101)
select top 10 pt.pt_id, pt.last_name
fromsmsmir.mir_acct a join smsmir.mir_pt pt on (a.src_sys_id = pt.src_sys_id
and a.pt_id = pt.pt_id
and a.from_file_ind = pt.from_file_ind
[Code] ....
Seems I should be able to not test the last name after the turnover date, but I can't figure out how.
Get output of SQL Procedure and assign it to a variable used in WHERE Clause
Later I want to use this variable in my code in the WHERE Clause
Declare @ProjectNo nvarchar(10)
--Now I want to assign it to output of a storedprocedure which returns only 1 value and use it in the below SELECT query.
SELECT ID from TABLEA where Project in (@ProjectNo)
How to do it. How to assign @ProjectNo to output of storedProcedure called 'GetProjNumber'
I have recently started working with a new group of people and I find myself doing a lot of reporting. While doing this reporting I have been writing a TON of sql. Some of my queries were not performing up to par and another developer in the shop recommended that I stay away from the "GROUP BY" clause.
Backing away from the "GROUP BY" clause and using "INNER SELECTS" instead as been more effective and some queries have gone from over 1 minute to less that 1 second.
Obviously if it works then it works and there is no arguing that point. My question to the forum is more about gather some opinions so that I can build an opinion of my own.
If I cannot do a reasonable query of a couple of million records using a group by clause what is the problem and what is the best fix?
Is the best fix to remove the "GROUP BY" and write a query that is a little more complex or should I be looking at tuning the database with more indexes and statistics?
I want to make sure that this one point is crystal clear. I am not against following the advice of my coworker and avoiding the "GROUP BY" clause. I am only intersted in listening to a few others talk about why the agree or disagree with my coworked so that I can gain a broader understanding.
Hi There !!
To finetune performance for some of our queries,
I have come across suggestions to use
- JOINS instead of WHERE clause wherever possible
- and avoid using Aliases
Although Avoiding aliases looks reasonable I am yet to be convinced about JOINS replacing the WHERE CLAUSE . What is the experts take on this one ????
Also,
I checked the estimated plan in SQL server by running the following 2 queries into my Query Designer
tables : dba ( empid, empname )
project ( project_empid references dba.empid, project_name )
USING A WHERE CLAUSE and Alias
-------------------------
select a.emp_name from dbo.dba a, dbo.project b
where
a.empid =b.project_emp
and b.project_name is not null
USING A JOIN
-----------------
select emp_name from dbo.dba
as
a inner JOIN dbo.project
ON empid = dbo.project.project_emp
AND dbo.project.project_name is not NULL
******
I find from the Estimated plan that both the queries give the same amount of cost ( I/O, CPU, et all ) :shocked:
Any comments/ suggestions.
Thanks,
Have a great time
-Ranjit.
-------------------------------------
It pays to be honest to your DBA
Consider the following two functionally identical example queries:Query 1:DECLARE @Name VARCHAR(32)SET @Name = 'Bob'SELECT * FROM EmployeesWHERE [Name] = CASE WHEN @Name IS NULL THEN [Name] ELSE @Name ENDQuery 2:SELECT * FROM Employees WHERE [Name] = 'Bob'I would expect SQL Server to construct an identical QEP under the hoodfor these two queries, and that they would require essentially thesame amount of time to execute. However, Query 1 takes much longer torun on my indexed table of ~300,000 rows. By "longer", I mean thatQuery 1 takes about two seconds, while Query 2 returns almostinstantly.Is there a way to implement a conditional WHERE clause withoutsuffering this performance hit? I want to avoid using the IF...THENmethod because I frequently require several optional parameters in theWHERE clause.Thanks!Jared
View 6 Replies View RelatedHi all,Just wondering if anyone can tell me if an order by clause on a selectquery would have any impact on the time it takes to retrieve results?Essentially I'm selecting Top 1 out of a table via various criteriaand currently getting it back without an order by clause. The order bywould only include the column that has the clustered primary index onit.Can anyone tell me if in theory this will slow the query down?Many thanks in advance!Much warmth,Murrau
View 1 Replies View RelatedI've been experiencing difficulty with pulling records using a where clause date range. I'm using this:
select *
from dbo.ACCTING_TRANSACTION_hISTORY
where ath_postype = 'NTC' or ath_postype='NTD' and
ath_postdate >= '2013-01-01 00:00:00' and
ath_postdate <= '2013-01-05 23:59:59'
I've also tried variations of this without the time portion of the ath_postdate field (of type datetime) , but it still seems to be pulling records from 2009, etc.
I am wanting to get the job name based on sys.sysProcesses.[Program_name] column. Why is this query not returning any results even though the 2nd substringed guids are found the the sysJobs table?
SELECTCASE
WHEN RTRIM([program_name]) LIKE 'SQLAgent - TSQL JobStep (Job %' THEN J.Name
ELSE RTRIM([program_name])
END ProgramName
, Val1.UqID
, Val1.UqIDStr
[Code] ......
We have a medium sized database with the next tables:
- PA: 525000 records
- PR: 780000 records
- R: 1000 records
- B: 45 records
PA: PK = PAARDCODE
PR: PK = PAARDREGISTERCODE
PR: FK = PAARDCODE
PR: FK = REGISTERCODE
R: PK = REGISTERCODE
R: FK = BOEKCODE
B: PK = BOEKCODE
When I group by B.BOEKCODE the query lasts: 10 (or more when 'where' option is added) seconds
When I group by R.BOEKCODE the query lasts less than 2 seconds.
SELECT B.BOEKOMSCHRIJVING, B.BOEKCODE -- or R.BOEKCODE
FROM PA
INNER JOIN PR ON PA.PAARDCODE = PR.PAARDCODE
INNER JOIN R ON R.REGISTERCODE = PR.REGISTERCODE
INNER JOIN B ON R.BOEKCODE = B.BOEKCODE
GROUP BY BOEKOMSCHRIJVING, B.BOEKCODE -- or R.BOEKCODE
ORDER BY BOEKOMSCHRIJVING Why is the option of B.BOEKCODE a lot slower compared to R.BOEKCODE?
I want to change Set clause of Update Statement dynamically based on some condition.
Basically i have 2 Update statments having same FROM clause and same JOIN clause.
Only diff is SET clause and 1 Where condition.
So i am trying to combine 2 Update statements into 1 and trying to avoid visit to same table twice.
Update t
Set CASE **WHEN Isnull(td.IsPosted, 0) = 0
THEN t.AODYD = td.ODYD**
*ELSE t.DAODYD = td.ODYD*
END
From #ReportData As t
Join @CIR AS tmp On t.RowId = tmp.Max_RowId
[Code] ....
But CASE statement is not working...
Everything is flowing smoothly for the SQL Server Database I have, except one type of retrieval and that is when the where clause has a range of data values to do the retrieval then the performance is terrible. I cannot anticipate every range. There are indexes on the table to try to help; however, nothing seems to help. Has anyone had a similiar problem? Any suggestions to improve performance?
Thanks, Mary
Hi!
I have just installed Microsoft OLEDB provider for DB2 on a SQL server 2005. I created a Linked server against our DB2 V.8 Z/OS database. I tested the connection via execution of a simple select call, something like:
SELECT FIELD_A FROM DB2SRV.DB2DB.CREATOR_A.TABLE_A
WHERE FIELD_A='ABC'
I traced the call on the DB2 site. The SQL running on DB2 site was to my surprise without the €œwhere clause€?:
SELECT FIELD_A FROM DB2DB.CREATOR_A.TABLE_A
So, all rows are moved to SQL server before the where clause is executed, resulting in bad performance. The index on FIELD_A is not used and so on €¦ !
If anyone out there has an idea of what could be wrong, please let me know!
NB. I know that by using OPENQUERY pass-through query, all execution is done on the DB2 site.
SQL Server 2008 r2...
I have a query which does 3 selects and Union ALLs each to get a final result set. The performance is unacceptable - takes around a minute to run. If I remove the Union All so that the result sets are returned individually it returns all 3 from the query in around 6 seconds (acceptable performance).
Any way to join the result sets together without using Union All.
Each result set has exactly the same structure returned...
Query below [for reference]...
WITH cte AS (
SELECT A.[PoleID], ISNULL(B.[IsSpanClear], 0) AS [IsSpanClear], B.[SurveyDate], ROW_NUMBER() OVER (PARTITION BY A.[PoleID] ORDER BY B.[SurveyDate] DESC) rownum
FROM[UT_Pole] A
LEFT OUTER JOIN [UT_Surveyed_Pole] B ON A.[PoleID] = B.[PoleID]
[Code] .....
I have a quite big SQL query which would be nice to be used using UNION betweern two Select and Where clauses. I noticed that if both Select clauses have Where part between UNION other is ignored. How can I prevent this?
I found a article in StackOverflow saying that if UNION has e.g. two Selects with Where conditions other one will not work. [URL] ....
I have installed SQL Server 2014 and I tried to use tricks mentioned in StackOverflow's article but couldn't succeeded.
Any example how to write two Selects with own Where clauses and those Selects are joined with UNION?
Hi, can anyone shed some light on this issue?SELECT Status from lupStatuswith a normal query it returns the correct recordcountSELECT Status from lupStatus GROUP BY Statusbut with a GROUP By clause or DISTINCT clause it return the recordcount= -1
View 3 Replies View RelatedI am working with a vendor on upgrading their application from SQL2K to SQL2K5 and am running into the following.
When on SQL Server 2000 the following statement ran without issue:
UPDATE dbo.Track_ID
SET dbo.Track_ID.Processed = 4 --Regular 1 leg call thats been completed
WHERE Processed = 0 AND LegNum = 1
AND TrackID IN
(
SELECT TrackID
FROM dbo.Track_ID
GROUP BY TrackID
HAVING MAX(LegNum) = 1 AND
TrackID + 'x1' IN
(
SELECT
dbo.Track_ID.TrackID + 'x' + CONVERT(NVARCHAR(2), COUNT(dbo.Track_ID.TrackID))
FROM dbo.Track_ID INNER JOIN dbo.transactions
ON dbo.Track_ID.SM_ID = dbo.transactions.sm_session_id
GROUP BY dbo.Track_ID.TrackID
)
)
Once moved to SQL Server 2005 the statement would not return and showed SOS_SCHEDULER_YIELD to be the waittype when executed. This machine is SP1 and needs to be upgraded to SP2, something that is not going to happen near time.
I changed the SQL to the following, SQL Server now runs it in under a second, but now the app is not functioning correctly. Are the above and the following semantically the same?
UPDATE dbo.Track_ID
SET dbo.Track_ID.Processed = 4 --Regular 1 leg call thats been completed
WHERE Processed = 0 AND LegNum = 1
AND TrackID IN
(
SELECT TrackID
FROM dbo.Track_ID
WHERE TrackID + 'x1' IN
(
SELECT dbo.Track_ID.TrackID + 'x' + CONVERT(NVARCHAR(2), COUNT(dbo.Track_ID.TrackID))
FROM dbo.Track_ID INNER JOIN dbo.transactions
ON dbo.Track_ID.SM_ID = dbo.transactions.sm_session_id
GROUP BY dbo.Track_ID.TrackID
)
GROUP BY TrackID
HAVING MAX(LegNum) = 1
)
1. Use mssql server agent service to take the schedule
2. Use a .NET windows service with timers to call SqlClientConnection
above, which way would be faster and get a better performance?
2 examples:
1) Rows ordered using textual id rather than numeric id
Code Snippet
select
cast(v.id as nvarchar(2)) id
from
(
select 1 id
union select 2 id
union select 11 id
) v
order by
v.id
Result set is ordered as: 1, 11, 2
I expect: 1,2,11
if renamed or removed alias for "cast(v.id as nvarchar(2))" expression then all works fine.
2) SQL server reject query below with next message
Server: Msg 169, Level 15, State 3, Line 16
A column has been specified more than once in the order by list. Columns in the order by list must be unique.
Code Snippet
select
cast(v.id as nvarchar(2)) id
from
(
select 1 id
union select 2 id
union select 11 id
) v
cross join (
select 1 id
union select 2 id
union select 11 id
) u
order by
v.id
,u.id
Again, if renamed or removed alias for "cast(v.id as nvarchar(2))" expression then all works fine.
It reproducible on
Microsoft SQL Server 2000 - 8.00.2039 (Intel X86) May 3 2005 23:18:38 Copyright (c) 1988-2003 Microsoft Corporation Developer Edition on Windows NT 5.1 (Build 2600: Service Pack 2)
and
Microsoft SQL Server 2005 - 9.00.3042.00 (Intel X86) Feb 9 2007 22:47:07 Copyright (c) 1988-2005 Microsoft Corporation Developer Edition on Windows NT 5.1 (Build 2600: Service Pack 2)
In both cases database collation is SQL_Latin1_General_CP1251_CS_AS
If I check quieries above on database with SQL_Latin1_General_CP1_CI_AS collation then it works fine again.
Could someone clarify - is it bug or expected behaviour?
Hello Everyone,I have a very complex performance issue with our production database.Here's the scenario. We have a production webserver server and adevelopment web server. Both are running SQL Server 2000.I encounted various performance issues with the production server with aparticular query. It would take approximately 22 seconds to return 100rows, thats about 0.22 seconds per row. Note: I ran the query in singleuser mode. So I tested the query on the Development server by taking abackup (.dmp) of the database and moving it onto the dev server. I ranthe same query and found that it ran in less than a second.I took a look at the query execution plan and I found that they we'rethe exact same in both cases.Then I took a look at the various index's, and again I found nodifferences in the table indices.If both databases are identical, I'm assumeing that the issue is relatedto some external hardware issue like: disk space, memory etc. Or couldit be OS software related issues, like service packs, SQL Serverconfiguations etc.Here's what I've done to rule out some obvious hardware issues on theprod server:1. Moved all extraneous files to a secondary harddrive to free up spaceon the primary harddrive. There is 55gb's of free space on the disk.2. Applied SQL Server SP4 service packs3. Defragmented the primary harddrive4. Applied all Windows Server 2003 updatesHere is the prod servers system specs:2x Intel Xeon 2.67GHZTotal Physical Memory 2GB, Available Physical Memory 815MBWindows Server 2003 SE /w SP1Here is the dev serers system specs:2x Intel Xeon 2.80GHz2GB DDR2-SDRAMWindows Server 2003 SE /w SP1I'm not sure what else to do, the query performance is an order ofmagnitude difference and I can't explain it. To me its is a hardware oroperating system related issue.Any Ideas would help me greatly!Thanks,Brian T*** Sent via Developersdex http://www.developersdex.com ***
View 2 Replies View RelatedI am using web developer 2008, while connecting to I wanted to fetch data from Lotus notes database file, for this i used notesql connector, while connectiong to notes database i am fetting error
ERROR [42000] [Lotus][ODBC Lotus Notes]Table reference has to be a table name or an outer join escape clause in a FROM clause
I have already checked that database & table name are correct, please help me out
How i can fetch the lotus notes data in my asp.net pages.
I am using web developer 2008, while connecting to I wanted to fetch data from Lotus notes database file, for this i used notesql connector, while connectiong to notes database i am fetting error
ERROR [42000] [Lotus][ODBC Lotus Notes]Table reference has to be a table name or an outer join escape clause in a FROM clause
I have already checked that database & table name are correct, please help me out
How i can fetch the lotus notes data in my asp.net pages.
Hi,
What is HAVING clause equivalent in the following oracle query, without the combination of "GROUP BY" clause ?
eg :
SELECT SUM(col1) from test HAVING col2 < 5
SELECT SUM(col1) from test WHERE x=y AND HAVING col2 < 5
I want the equivalent query in MSSQLServer for the above Oracle query.
Also, does the aggregate function in Select column(here the SUM(col1)) affect in anyway the presence of HAVING clause?.
Thanks,
Gopi.
How Can I use Top Clause with GROUP BY clause?
Here is my simple problem.
I have two tables
Categories
Products
I want to know Top 5 Products in CategoryID 1,2,3,4,5
Resultset should contain 25 Rows ( 5 top products from each category )
I hope someone will help me soon.
Its urngent
thanks in advance
regards
Waqas
hi..
i have basic question like
what is differance between conditions put in ON clause and in WHERE clause in JOINS????
see conditions that shown in brown color
select d1.SourceID, d1.PID, d1.SummaryID, d1.EffectiveDate,
d1.Audit, d1.ExpirationDate, d1.Indicator
from[DB1].[dbo].[Implicit] d1 inner join [DB2].[dbo].[Implicit] d2
on d1.SummaryID=d2.SummaryID
AND d1.ListType = d2.ListType
AND (d1.EffectiveDate <= d2.ExpirationDate or d2.ExpirationDate is null)
AND (d1.ExpirationDate >= d2.EffectiveDate or d1.ExpirationDate is null)
whered1.ImplicitID >= d2.ImplicitID AND
(d1.SourceID<>d2.SourceID
OR (d1.SourceID IS NULL AND d2.SourceID IS NOT NULL)
OR (d1.SourceID IS NOT NULL AND d2.SourceID IS NULL)
)
select d1.SourceID, d1.PID, d1.SummaryID, d1.EffectiveDate,
d1.Audit, d1.ExpirationDate, d1.Indicator
from[DB1].[dbo].[Implicit] d1 inner join [DB2].[dbo].[Implicit] d2
on d1.SummaryID=d2.SummaryID
AND d1.ImplicitID = d1.ImplicitIDAND d1.ListType = d2.ListType
AND (d1.EffectiveDate <= d2.ExpirationDate or d2.ExpirationDate is null)
AND (d1.ExpirationDate >= d2.EffectiveDate or d1.ExpirationDate is null)
whered1.ImplicitID >= d2.ImplicitID AND
(d1.SourceID<>d2.SourceID
OR (d1.SourceID IS NULL AND d2.SourceID IS NOT NULL)
OR (d1.SourceID IS NOT NULL AND d2.SourceID IS NULL)
)
another thing...
if we put AND d1.ImplicitID = d1.ImplicitID condition in second query then shall we remove
d1.ImplicitID >= d2.ImplicitID from WHERE clause????
Hi everyone,
I saw some queries where SQL inner join clause and the where clause is used at the same time. I knew that "on" is used instead of the "where" clause. Would anyone please exaplin me why both "where" and "on" clause is used in some sql Select queries ?
Thanks