Does anyone have a general rule or guide on when to use this SQL 2000 option when creating indexes? I was thinking generally on nonclustered indexes where the column would be unique and incremental and usually filtered on by range and often used in the order by clause. Such as columns of datetime or integers datatypes. Thanks.
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Hey guys, I have a view with dates (TheDate) meant to be arranged in descending order. When I 'Execute SQL' while in the view, the DESC order works just fine and shows up with the latest date first going down. However, once I 'OPEN VIEW' the order keeps defaulting to ASCending order.
How do I keep it in DESC order for viewing? Here's the statement:
SELECT TOP (100) PERCENT TheDate
FROM dbo.MyDates
ORDER BY TheDate DESC
hi, i have headers at the top of my list and would like for people to click the pubs link and it orders the pubs alphabetically descending and when they click again to ascend also to do this with towns and addresses and postcodes?!
can someone please help?
J x
Hi all,I have a SQL statement that allows paging and dynamic sorting of thecolumns, but what I can't figure out without making the SQL a dynamicstring and executing it, or duplicating the SQL statement between anIF and ELSE statement.Following is the SQL statement;set ANSI_NULLS ONset QUOTED_IDENTIFIER ONgoALTER PROCEDURE [dbo].[sp_search]@search VARCHAR( 80 ), @startRow INT = 1, @endRow INT = NULL, @postcode AS CHAR( 4 ) = NULL, @suburb AS VARCHAR( 40 ) = NULL, @stateIdentity AS TINYINT = NULL, @fromLatitude AS REAL = NULL -- latitude the user is located in, @fromLongitude AS REAL = NULL -- longitude the user is located in, @sort TINYINT = 1ASBEGINSET NOCOUNT ON;DECLARE @calculateDistance BIT;SET @calculateDistance = 0;-- get the longitude and latitude if requiredIF ( NOT @postcode IS NULL )BEGINSELECTDISTINCT@fromLatitude = latitude, @fromLongitude = longitudeFROMtbl_postalcodeWHERE(postalcode = @postcode)SET @calculateDistance = 1ENDELSE IF ( NOT @suburb IS NULL AND NOT @stateIdentity IS NULL )BEGINSELECTDISTINCT@fromLatitude = latitude, @fromLongitude = longitudeFROMtbl_localityWHERE(locality = @suburb)AND(stateIdentity = @stateIdentity)SET @calculateDistance = 1END/*ELSE IF ( @fromLatitude IS NULL AND @fromLongitude IS NULL )BEGINRAISERROR( 'You need to pass a valid combination to this storedprocedure, example: postcode or suburb and state identity or longitudeand latitude', 18, 1 );END*/SELECT D1.[row], D1.[totalRecordCount], D1.[classifiedIdentity], D1.[title], D1.[summary], D1.[price], D1.[locality], D1.[state], D1.[postcode], D1.[addedLast24], D1.[dateStamp], D1.[t2Rank], D1.[t3Rank], D1.[tRank], D1.[distance], F.[originalName], F.[extension], F.[uniqueName]FROM(-- derived tableSELECT ROW_NUMBER() OVER ( ORDER BY CASE @sort WHEN 0 THENCAST( COALESCE( t2.RANK, 0 ) + COALESCE( t3.RANK, 0 ) AS CHAR( 5 ) )WHEN 1 THEN C.title WHEN 2 THEN CAST( CEILING( [dbo].[fn_calculateDistance] ( @fromLatitude, @fromLongitude, L.latitude,L.longitude ) ) AS CHAR( 9 ) ) WHEN 3 THEN ( C.locality + ' ' +C.state ) WHEN 4 THEN CAST( C.price AS CHAR( 10 ) ) END ASC ) AS row, COUNT( * ) OVER() AS totalRecordCount, C.[classifiedIdentity], C.[title], C.[summary], C.[price], C.[locality], C.[state], C.[postcode], CASE WHEN ( C.[dateStamp] >= DATEADD( day, -1, GETDATE() ) )THEN 1 ELSE 0 END AS addedLast24, C.[dateStamp]/* , t1.RANK AS t1Rank */, t2.RANK AS t2Rank, t3.RANK AS t3Rank, /* COALESCE( t1.RANK, 0 ) + */ COALESCE( t2.RANK, 0 ) +COALESCE( t3.RANK, 0 ) AS tRank, CASE @calculateDistance WHEN 1 THEN CEILING( [dbo].[fn_calculateDistance] ( @fromLatitude, @fromLongitude, L.latitude,L.longitude ) ) ELSE 0 END AS distanceFROM [tbl_classified] AS CINNER JOINtbl_locality LONC.localityIdentity = L.localityIdentity/* LEFT OUTER JOINCONTAINSTABLE( tbl_category, title, @keyword ) ASt1ON FT_TBL.categoryIdentity = t1.[KEY] */LEFT OUTER JOINCONTAINSTABLE( tbl_classified, title, @search ) ASt2ON C.classifiedIdentity = t2.[KEY]LEFT OUTER JOINCONTAINSTABLE( tbl_classified, description,@search ) AS t3ON C.classifiedIdentity = t3.[KEY]WHERE ( /* COALESCE( t1.RANK, 0 ) + */COALESCE( t2.RANK, 0 ) +COALESCE( t3.RANK, 0 ) ) != 0) AS D1LEFT OUTER JOINtbl_classified_file CFOND1.classifiedIdentity = CF.classifiedIdentityLEFT OUTER JOINtbl_file FONF.fileIdentity = CF.fileIdentityWHERE( row >= @startRow )AND( @endRow IS NULL OR row <= @endRow )ENDThe part I'm having trouble with is making the sort order in thefollowing line dynamicORDER BY CASE @sort WHEN 0 THEN CAST( COALESCE( t2.RANK, 0 ) +COALESCE( t3.RANK, 0 ) AS CHAR( 5 ) ) WHEN 1 THEN C.title WHEN 2 THENCAST( CEILING( [dbo].[fn_calculateDistance] ( @fromLatitude,@fromLongitude, L.latitude, L.longitude ) ) AS CHAR( 9 ) ) WHEN 3 THEN( C.locality + ' ' + C.state ) WHEN 4 THEN CAST( C.price ASCHAR( 10 ) ) END ASCany help would be greatly apprecaited.Thanks
View 1 Replies View RelatedI am using sql statement like SELECT CREATEDBY,FIRSTNAME,BUSINESS,NOTES,NOTESDATE FROM BUSINESS ORDER BY NOTESDATE DESC, CREATEDBY ASC
But NotesDate is sorting descending order, but only sorting based on the date and month not on year
Please help me
There is a index: CustomerInfo_1
with keys: customerId, EnteryDate DESC
I could not find where the order of index key (i.e. whether the key is ascending or descending) is stored?
I tried system tables such as sysindexes and sysindexkeys tables. But could not find it.
Any help in this regard will be truly appreciated.
Thank you.
Regards,
Anuj Goyal
There is a index: CustomerInfo_1
with keys: customerId, EnteryDate DESC
I could not find where the order of index key (i.e. whether the key is ascending or descending) is stored?
I tried system tables such as sysindexes and sysindexkeys tables. But could not find it.
Any help in this regard will be truly appreciated.
Thank you.
Regards,
Anuj Goyal
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.
I am trying to order by the field and direction as provided by input parameters @COLTOSORTBY and @DIR while using a CTE and assigning Row_Number, but am running into syntax errors.
Say I have a table called myTable with columns col1,col2,col3,
Here's what I'm trying to do
with myCTE AS
(
Select
col1
,col2
,col3
,row_number() over (order by
case when(@DIR = 'ASC') then
case when @COLTOSORTBY='col1' then col1 asc
when @COLTOSORTBY='col2' then col2 asc
else col3 asc
end
else
case when @COLTOSORTBY='col1' then col1 desc
when @COLTOSORTBY='col2' then col2 desc
else col3 desc
end
end
from myTable
)
Please let me know what i can do with minimal code repetition and achive my goal of dynamically sorting column and direction. I do not want to use dynamic SQL under any circumstance.
Thanks.
I have a clustered index that consists of 3 int columns in this order: DateKey, LocationKey, ItemKey (there are many other columns in this data warehouse table such as quantities, prices, etc.).
Now I want to add a non-clustered index on just one of the other columns, say LocationKey, like this:
CREATE INDEX IX_test on TableName (LocationKey)
I understand that the clustered index keys will also be added as key columns to any NC indexes. So, in this case the NC index will also get the other two columns from the clustered index added as key columns. But, in what order will they be added?
Will the resulting index keys on this new NC index effectively be:
LocationKey, DateKey, ItemKey
OR
LocationKey, ItemKey, DateKey
Do the clustering keys get added to a NC index in the same order as they are defined in the clustered index?
I want to make an index with the following columns, actually together they constitute the PK of the table so the index is created automatically.
The question is witch sort order is the best to have if I want to fetch all rows for one date and one resource? And why?
WHERE Resource = "Car 1" AND Date = "2013-03-03"
Resource, Date, Time
Or
Date, Time, Resource
Below is an example with tree resources, but in reality there can be a lot more and also years of dates.
Car 1, 2013-03-03, 10.00
Car 1, 2013-03-03, 11.00
Car 1, 2013-03-03, 12.00
Car 1, 2013-03-04, 10.00
[Code] ......
Is there a dynamic management view or system procedure which I can use to find out what columns are in an index, what columns are as an INCLUDE in the index and whether or not the column(s) are ascending or descending. This is excluding the utilities I already know about below:
sys.indexes
sys.index_columns
sp_helpindex
dm_db_index_physical_stats
dm_db_index_operational_stats
I only ask because it is a pain to look through the sys.indexes and sys.index_columns tables every time I want to know about what columns are in the index created. I also know that scripting the index would give me the information I need but there must be a better way.
Many Thanks
I have a table "Client" that has two columns: "ClientID" and "ProductID". I created on clustered index on ClientID and when I opened the table in the management studio, I saw the table was in the order of ClientID.
Then I added another non-clustered index on ProductID. When I open the table again, it is in the order of ProductID. Shouldn't the table always be in the order of clustered index? Non-clustered index should be a structure outside of the table itself? Did I do anything wrong?
Thanks for any hint.
Hi,I created a composite index (lastname, firstname). I know the followingqueries will use this index:WHERE lastname = ...WHERE lastname = ... AND firstname = ...Also this won't use the index:WHERE firstname = ...But how about: WHERE firstname = .. AND lastname = ...And why?Thanks a lot,Baihao--Posted via Mailgate.ORG Server - http://www.Mailgate.ORG
View 13 Replies View RelatedHi allI recently noticed when trying to optimise a major query of a chess websiteI am the webmaster of, that adding an order by for "gamenumber" which is aclustered index field as in for example "order by timeleft desc, gamenumberdesc" actually speeded up the queries and reduced sql server 2000 timeouts.I have an ASP error log and I am fairly sure that a dramatic reduction insql server timeouts is simply attributed to adding an extra seeminglyredundant order by field - which is the clustered index. Is this phenomenaat all possible or is it my imagination?!Other special attributes of the query includes the use of "Top" to obtain amaximum specified number of rows. Perhaps it is just the uniquecharacteristics of the query, but I would have thought that the less orderby fields would imply faster performance. Has anyone else noticed that aseemingly redundant order by column on for example the clustered indexcolumn, can actually help speed up queries?!Best wishesTryfon GavrielWebmasterwww.chessworld.net
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I have 2 columns in a table namely ColA and ColB.all DML operations are through views n every view has
Where clause i.e where ColA=€?€? with check option .
All most all my DML queries are using where clause on ColB
Where ColB=€?€?
Now my question is I have a clusted index on both ColA and ColB.in which order I have to create cluster index .
i.e ColA ASC,ColB ASC or ColB ASC,ColA ASC.
Is there any performance gain we can achieve with their order
Hi,
I want to ask a basic question, that is
IN WHAT ORDER A CLUSTERED INDEX SORT THE DATA IN THE COLUMN????
Somewhere in the MSDN library I read the following line:
"A clustered index physically sorts the table's contents in the order of the specified index columns"
But Sorting means it will be in ASCENDING ORDER (ASC) or It will be in DESCENDING ORDER (DESC)
So my question is lets suppose a column on which the cluistered index is defined and it contains character data liek abcd so in wht order it will sort the data alphabetically ASC or DESC
or
If the same above case with integer type of values, if column having integer values then in wht order the data in the table will be sorted.
??????
Thanks..!!!
We are using partitioned unique indexes on partitioned tables. When the Unique Index is built, should the column the index is partitioned by be the top (leftmost) column in the index? While this violates cardinality, it makes sense (at least to me) that the first thing the query execution would do is figure out which partition(s) contain the result set, then filter from there.
What do you guys think? Is there any documentation on optimizing partitioned indexes?
Hi
I was going through the book by Kalen Delaney where she has mentioned the following paragpraph in Chapter 7 (Index Internals):
Many documents describing SQL Server indexes will tell you that the clustered index physically stores the data in sorted order. This can be misleading if you think of physical storage as the disk itself. If a clustered index had to keep the data on the actual disk in a particular order, it could be prohibitively expensive to make changes. If a page got too full and had to be split in two, all the data on all the succeeding pages would have to be moved down. Sorted order in a clustered index simply means that the data page chain is logically in order.
Then I read the book on SQL Server 2000 (on Perf Tuning) by Ken England. He says the clustered index stores data in physical order and any insert means moving the data physically. Also the same statement is echoed on the net by many articles.
What is the truth? How are really clustered index stored? What does physical order in the above statement really mean?
Regards
SanjaySi
Want to check my thinking with you folks...
I have a table with a clustered composite index, consisting of 3 columns, which together form a unique key. For illustration, the columns are C1, C2 & C3.
Counts of distinct values for columns are C1 425, C2 300,000 & C3 4,000,000
C3 is effectively number of seconds since 01/01/1970.
The usage of the table is typically, insert a row, do something else, then update it.
Currently, the index columns are ordered C3,C1,C2. Fill factor of 90%.
My thinking is that this composite index is better ordered C1,C2,C3.
My reasoning is that having C3 as the leading column, biases all the inserts towards one side of the indexes underlying B-tree, causing page splits. Also, there'll be a bunch of "wasted" space across the tree, as the values going into C3 only ever get bigger (like an identity), so the space due to the fill factor in lower values never gets used.
Welcome your thoughts.
Hi all,
I'm getting this "invalid descriptor index" exception while trying to fetch a record from the table.
The query is "select * from <tablename> where <columnname> = 'xyz'". The column name is correct and indeed a record with 'xyz' value exists. The record is getting fetched too...! But I'm having this particular error while trying to retrieve a couple of fields with rs.getString().
The order of columns in the table is same as the order in which I'm retrieving them. And I'm not facing any problem retrieving another field which has width of 200 characters.
I'll be very grateful indeed if someone can help me out of this particular problem...
Cheers, mates!
I upsized an access database with a key / index on ordernumber and linenumber.
However if I open the table in the Management Studio the records aren't ordered this way (same goes for select * from table) I get:
Ordernumber
Linenumber
200724001
37
200724004
3
200724006
33
200724001
3
200724011
19
200724014
5
200724006
37
200724011
19
200724006
28
Same goes for my crystal reports files, since the records aren't ordered by ordernumber / linenumber all my formulas go bezerk..
Am I wrong thinking the records should be ordered according to the prim. index?
Please help because I don't want to have to change all my 40+ reports to include an "ORDER BY"
Best regards,
Mike
Does column order matter when creating a table? For example, Should NOT NULL columns always come before NULL columns? Should most frequently used columns always be near the top? What about text, ntext and image data types? Should they always appear near the end of the column order?
View 1 Replies View RelatedI am creating an index on a table wit 35 million records but I get the error
'TT_ObjPerformance' table- Unable to create index 'IX_TT_ObjPerformance_CACode'. Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.
How can I get the index created?
ThanksSQL Server newbie
Hi,
Trying to optimize a query but not sure what to do. I have this query on which I ran an exec plan,
SET NOCOUNT ON;
SELECT qaTestSuite.TestSuiteID, qaTestSuite.TestSuiteStart, qaTestSuite.TestInterface, qaTestSuite.TestVersion, qaTests.TestMachine, qaTestSuite.TestClientMachine, qaTests.TestLogin, qaTests.TestLabel,
qaTestSuite.TestCLPs, qaTestSuite.TestSuiteEnd, qaTests.TestID, qaTests.TestIDInternal, qaTests.TestStart,
qaTests.TestName, qaTests.TestTier, qaTests.TestNo, qaTests.TestWFBCalled, qaTests.TestWFBTime,
qaTests.TestSearches, qaTests.TestSearchesTime, qaTests.TestResult, qaTests.TestEnd, qaTestMssgs.TestMssgsID,
qaTestMssgs.TestMssgTime, qaTestMssgs.TestMssgType, qaTestMssgs.TestMessage, qaTestSuite.TestMode
FROM qaTestSuite with(NOLOCK) INNER JOIN
qaTests with(NOLOCK) ON qaTestSuite.TestSuiteID = qaTests.TestSuiteID INNER JOIN
qaTestMssgs with(NOLOCK) ON qaTests.TestID = qaTestMssgs.TestID
order by qaTestSuite.TestSuiteStart DESC
and it gives me the following results:
Use a Bookmark (RID or Clustering Key) to look up the corresponding row in the Table or Clustered Index.
Physical Op: Bookmark Lookup
Logical Op: Bookmark Lookup
Est. Row Count: 128
Est. Row Size: 4760
Est. I/O Cost: 0.368
Est. CPU Cost: 0.000141
Est. Execs: 1.0
Est. Cost: 0.368888(89%)
Est. Subtree Cost:.415
Argument:
BOOKMARK:([Bmk1004]), OBJECT:([QAMaster].[dbo].[qaTestMssgs]) WITH PREFETCH
I have no idea what to do with that. Anyone have any clues? What I found online was that I should make a Covering Index, but I didn't find
any patterns on how to do that. Any one have ideas of how to do this?
Thanks very much for your help!
--PhB
Hi
i am new to using this sql server 2000....this is a very simple question to all u guys.....i am just in a learning stage...so any help from u guys is really appreciable....
i need to create a table customers with the following columns...
identity column to self-populate as the primary key,
joindate, leavedate, custcode, empID.
This is the one i tried:
create table customers (id int primary key identity (1,1) not null,
joindate smalldatetime null,
leavedate smalldatetime null,
custcode varchar (10) not null,
empid int not null
)
is tht code correct only???
and i also want the below one :
Create indexes on the leavedate, custcode and empid columns.
how to create these indexes???
and wht happens when i create them(like is thr any advantage of creating indexes???)
thanks......
HiI tried the following from the help file...When you create or modify a unique index, you can set an option toignore duplicate keys. If this option is set and you attempt to createduplicate keys by adding or updating data that affects multiple rows(with the INSERT or UPDATE statement), the row that causes theduplicates is not added or, in the case of an update, discarded.For example, if you try to update "Smith" to "Jones" in a table where"Jones" already exists, you end up with one "Jones" and no "Smith" inthe resulting table. The original "Smith" row is lost because anUPDATE statement is actually a DELETE followed by an INSERT. "Smith"was deleted and the attempt to insert an additional "Jones" failed.The whole transaction cannot be rolled back because the purpose ofthis option is to allow a transaction in spite of the presence ofduplicates.But when I did it the original "Smith" row was not lost.I am doing something wrong or is the help file incorrect.Dan
View 3 Replies View RelatedIn SQL 2012.A query that joins 2 table, with order by clause doesn't get sorted and the result set is not ordered. This happens when some of the columns in the where criteria are in a unique index which is the index that is used for the join between the 2 tables, and all the columns in the unique index are in the where criteria.In the query plan there is no component for sort.The work around was to drop the unique index, or change it to a non-unique index. Once this was done, the execution plan was changed to add the sort component (even when the index was changed to non-unique and the join was still using this index).
View 4 Replies View RelatedI created table and also I define the primary key its okay
but when I generate the SQL script for that table its not
creating the primary key
CREATE TABLE [dbo].[table1] (
[emp_id] [int] NOT NULL ,
[emp_name] [char] (25) NULL ,
[emp_address] [nvarchar] (50) NULL
) ON [PRIMARY]
GO
PS: I want to use emp_id as primary key but its not defined in the sql script
Thankx a lot
have a 3rd party app (can't change) which has some bad sql. I have a table that is used in the sql which if I put a clustered (I had an index on the fields in the sql but it would ignore and table scan) will use and stop doing table scan. this is a million row table that is growing. the data going in is pretty mich insert only. I have a separate array and file group which I have moved indexes to last year. 2 questions
1. If I would make a clustered index on the separate RAID and file group, doesn't the table need to go with it. I thought the clustered index and table had to be on same File Group
2. If I do this anyone see any issues with moving this table and index on this file group
Hi Guys,
I have a SQL 2000 sp3a server on Windows 2000 sp4. Running dual proc server with hyper threading enabled, 3gb memory attached to a HP EVA 5000 SAN.
One of the tables is 67gb and contains 140,000,000 rows. Recently someone dropped the clustered indexe so i`m trying to put it back (i've dropped the non clustered indexes as no point leaving them there whilst clustered builds).
The problem i am having is the rebuild is taking forever!! It ran for 23 hours before someone rebooted the server (!). The database is currently recovering from the reboot but i need to work out what is causing the appalling performance so i can get the index rebuilt. There are no reported hardware problems.....
There are multiple file groups involved and i found i was getting an extent allocation rate of 1.5 extents a second and same for deallocation.
Any advice on how to trouble shoot this?
Hi,
I have created a very simple table. Here is the script:
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[IndexTable]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[IndexTable]
GO
CREATE TABLE [dbo].[IndexTable] (
[Id] [int] NOT NULL ,
[Code] [nvarchar] (50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL
) ON [PRIMARY]
GO
CREATE CLUSTERED INDEX [CusteredOnCode] ON [dbo].[IndexTable]([Id]) ON [PRIMARY]
GO
ALTER TABLE [dbo].[IndexTable] ADD
CONSTRAINT [PrimaryKeyOnId] PRIMARY KEY NONCLUSTERED
(
[Id]
) ON [PRIMARY]
GO
The records that i added are:
Id Code
1 a
2 b
3 aa
4 bb
Now when i query like
Select * from IndexTable
I expect the results as:
Id Code
1 a
3 aa
2 b
4 bb
as i have the clustered index on column Code.
But i m getting the results as:
Id Code
1 a
2 b
3 aa
4 bb
as per the primary key order that is a non clustered index.
Can anyone explain why it is happening?
Thanks
Nitin
I have a table called as A table :
CREATE TABLE [dbo].[A](
 [AutoID] [int] IDENTITY(1,1) NOT NULL,
 [ProID] [int] NOT NULL,
 [LID] [varchar](12) NOT NULL,
 [EventID] [varchar](12) NOT NULL,
 [HEventID] [varchar](12) NULL,Â
) ON [PRIMARY]Â Â Â
How I should creating the appropiate index for this table?AÂ few option that I think ok.
Opt 1 : creating a primary key on the autoID with create index . create non clustered index on ProID and EventID
Opt 2 : create a primary key on the autoID with non clustered index . create clustred index on ProID and EventID .
opt 3: create primary key on the ProID and EventID with clustered index.
I have read thru the article on the primary key, clustered and non clustered indexing. However when I want to applyied the indexing..I feel a bit lost.But among the 3 option.... what is the different..