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Good point. Personally I must learn to use that technique more often (started immediately to quote on a new thread  )
The need to optimize rises from a bad design.
My articles[ ^]
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Like Mika said, don't delete your message even if it has been answered. Others may want to chime in their thoughts/ideas later on, or learn from a question you have that was answered.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
"Not only do you continue to babble nonsense, you can't even correctly remember the nonsense you babbled just minutes ago." - Rob Graham
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hi,
I have created C++ application which create DSN with ODBC Microsoft text driver to use .csv file
as Database .
I want to change data type of some columns.So I tried
cmdstr = "ALTER TABLE table1 ALTER COLUMN RATE char(20)";
SQLExecDirect(hstmt, cmdstr, SQL_NTS);
But its give error as "syntax error in Alter Statement".
When we create DSN using ODBC wizard schema.ini file generate which contains the schema
information.But When I generate DSN by programmatically Schema.ini file not generate.
Pointer in this direction will be helpful for me.
Sunil
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try using:
ALTER TABLE table1 modify COLUMN RATE char(20)
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I wan to search sql server table to find any word contains some all the letter what should i do.
I'm using Asp.net vb to create web page. I create a text box I want to search for special letters.
I'm using sqldatasource to connect to sql server with the following procedure:
SELECT Name, Emai FROM Item WHERE (itemName = @itemName)
What should i do instead of (itemName = @itemName)
Thanks
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If it is letters in a series (rather than any word containing any of these letters) you can use
WHERE ItemName like '%xyz%'
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As in previous post use LIKE for simple pattern matching or if you need more logic for the search, use CONTAINS[^] predicate.
The need to optimize rises from a bad design.
My articles[ ^]
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Thanks for this help.I'm trying apply it on the asp.net web page there was an error occur.
cannot use a contains or free text predicate on table or indexed view "item" because it is not full-text indexed
What should i do
thanks
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y_mmohd wrote: cannot use a contains or free text predicate on table or indexed view "item" because it is not full-text indexed
therefore you can either create a full-text index on the column OR use the LIKE expression - as you have been told several times.
y_mmohd wrote: I'm trying apply it on the asp.net web page
is totally irrelevant, its your sql query that is wrong.
Bob
Ashfield Consultants Ltd
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I've got a query like this:
WITH CTE1 AS
(
SELECT * FROM TABLE WHERE A = @A
),
CTE2 AS
(
SELECT * FROM TABLE WHERE B = @B
)
SELECT * FROM
CTE1
CROSS JOIN
CTE2
The above query works fine for me and always returns cross join result of the two queries. The problem happens when one of those CTEs doesn't return any row and therefore the CROSS JOIN returns nothing as well. When only one of those CTEs return something, my expectation is to return the result of that CTE cross joined with null values. Do you know how I can achieve this purpose?
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Since cross join doesn't have any 'OUTER' option, the result is always all combinations from all sources. If any of the sources have 0 rows the size of the result set is 0.
I think you could use simple outer joins and unions to get desired rows. Something like:
SELECT *
FROM Table A LEFT OUTER JOIN Table B ON 1=1
WHERE ...
UNION
SELECT *
FROM Table A RIGHT OUTER JOIN Table B ON 1=1
WHERE ...
However, I would re-check the design of the data model since normally the need to cross join is very rare and may indicate a design problem.
The need to optimize rises from a bad design.
My articles[ ^]
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Hi All
I am writting an stored procedure to get the recently inserted records primary key as follows:
ALTER PROCEDURE [DBO].[AddEditUserMsgDetails]
(
@iJobID [INT]=NULL,
@iUserID [INT]=NULL,
@vFromName [VARCHAR](50)=NULL,
@vFromAddress [VARCHAR](50)=NULL,
@vSubject [VARCHAR](50)=NULL,
@iListID [INT]=NULL,
@vActualText [VARCHAR](100)=NULL
)
AS
BEGIN
IF @iJobId IS NULL OR @iJobId=0
BEGIN
INSERT INTO ezlMailJobs (iUserID,vFromName,vFromAddress,vSubject,iListID,vActualText)
VALUES (@iUserID,@vFromName,@vFromAddress,@vSubject,@iListID,@vActualText)
set @iJobID= @@Identity
select @iJobID
END
IF @iJobId IS NOT NULL
BEGIN
UPDATE ezlMailJobs SET iUserID=@iUserID,vFromName=@vFromName,vFromAddress=@vFromAddress,
vSubject=@vSubject,iListID=@iListID,vActualText=@vActualText
WHERE iJobId=@iJobId
END
IF @@ERROR=0
BEGIN
COMMIT TRAN
SELECT 1
END
ELSE
BEGIN
ROLLBACK TRAN
SELECT -1
END
As in the above stored procedure when ijobid is null or zero, It should execute insert statement and return recently inserted records ijobid else it should execute update statement. But as now it is executing insert statement and returning some garbage value. one more thing I have declared ijobid as identity.
I am unable to figure out the problem. Please help me.
Thanks
WAA
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If the jobid is null or 0 you are executing an insert AND an update
IF @iJobId IS NULL OR @iJobId=0
BEGIN
..do insert
<big>set @iJobID= @@Identity</big>
select @iJobID
END
IF @iJobId IS NOT NULL ------ YOU SET IT 2 LINES ABOVE
BEGIN
...do update etc
Also you have commit/rollback, but I don't see a begin tran?
Hope this helps
Bob
Ashfield Consultants Ltd
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Thanks for your reply
I found the solution, want to share with the needful.
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO
ALTER PROCEDURE [DBO].[AddEditUserMsgDetails]
(
@iJobID [NUMERIC]=NULL,
@iUserID [NUMERIC]=NULL,
@vFromName [VARCHAR](50)=NULL,
@vFromAddress [VARCHAR](50)=NULL,
@vSubject [VARCHAR](50)=NULL,
@iListID [NUMERIC]=NULL,
@vActualText [TEXT]=NULL
)
AS
BEGIN
SET NOCOUNT ON
DECLARE @Return [NUMERIC]
SET @Return=NULL
BEGIN TRAN
IF @iJobId IS NULL OR @iJobId=0
BEGIN
INSERT INTO table1 (iUserID,vFromName,vFromAddress,vSubject,iListID,vActualText)
VALUES (@iUserID,@vFromName,@vFromAddress,@vSubject,@iListID,@vActualText)
SET @Return= SCOPE_IDENTITY()
SELECT @Return AS iJobId
END
IF @iJobId IS NOT NULL
BEGIN
UPDATE table1 SET iUserID=@iUserID,vFromName=@vFromName,vFromAddress=@vFromAddress,
vSubject=@vSubject,iListID=@iListID,vActualText=@vActualText
WHERE iJobId=@iJobId
SELECT 0
END
IF @@ERROR=0
BEGIN
COMMIT TRAN
END
ELSE
BEGIN
ROLLBACK TRAN
SELECT -1
END
SET NOCOUNT OFF
END
GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO
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The best way to do this, in my opinion, is to use the SCOPE_IDENTITY() function. This function will return the most recent identity value created in the current scope. Returning the value for the current scope is important because if you have triggers firing that perform inserts the @@IDENTITY variable will return the last identity value created, even if it was from a different table because of a trigger. You should use:
set @iJobID = SCOPE_IDENTITY()
after the insert.
Keep It Simple Stupid! (KISS)
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Thanks a lot. Its working now.
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I read an article here[^] describing how to perform SQL operations in an atomic manner using transactions. I just do not understand what the usage of a transaction is in the following example (I didn't ask my question below that article because the author has not answered asked questions).
CREATE PROCEDURE addTitle(@title_id VARCHAR(6), @au_id VARCHAR(11),
@title VARCHAR(20), @title_type CHAR(12))
AS
BEGIN TRAN
INSERT titles(title_id, title, type)
VALUES (@title_id, @title, @title_type)
IF (@@ERROR <> 0) GOTO ERR_HANDLER
INSERT titleauthor(au_id, title_id)
VALUES (@au_id, @title_id)
IF (@@ERROR <> 0) GOTO ERR_HANDLER
COMMIT TRAN
RETURN 0
ERR_HANDLER:
PRINT 'Unexpected error occurred!'
ROLLBACK TRAN
RETURN 1
My question is, if the the first insert statement failed, why do we need to roll back it? No insertion to database happened, therefore we do not need to rollback anything! If I'm right, what's the problem with the following sproc:
CREATE PROCEDURE addTitle(@title_id VARCHAR(6), @au_id VARCHAR(11),
@title VARCHAR(20), @title_type CHAR(12))
AS
INSERT titles(title_id, title, type)
VALUES (@title_id, @title, @title_type)
IF (@@ERROR <> 0) GOTO ERR_HANDLER
INSERT titleauthor(au_id, title_id)
VALUES (@au_id, @title_id)
IF (@@ERROR <> 0) GOTO ERR_HANDLER
RETURN 0
ERR_HANDLER:
RETURN 1
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In your version if the second insert fails, then an orphaned title has been added without its associated author.
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You are right, I just figured it out 
Thank you
_
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I guess I found my answer, it's useful when the first statement succeeds and the second one doesn't. At that time we need to rollback the first successful statement.
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There are several considerations in both examples. Some of them are:
1. Transaction usage and scope: In the first example transaction is started and ended inside stored proc. Personally I don't feel this is a good way to handle transactions. Consider what would happen if the real world situation involves call to two stored procs. If both of them autonomously end transaction, there's no quarantee that the result is correct. This is why I always start and end transactions at calling side.
2. Why rollback if first statement fails: Even though the insert itself fails, transaction is started and DML is executed. This has resulted to resource usage. The only way to free those resources is to roll back the transaction (since there's no point to commit a failure).
So basically I would prefer the second version of the stored proc, but I also would ensure that it's executed inside a transaction. This would make it possible to have larger scope transactions and also to retry failed operations inside a transaction which is a very elemental requirement in certain system types.
Mika
The need to optimize rises from a bad design.
My articles[ ^]
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Re: your point 1
The only time I've written stored procedures was when I was using ad hoc ODBC statements (about ten years ago) and had no other way to do transactions.
Currently, with ADO.net, I can do transactions in my program so I don't use stored procedures at all.
However, a properly designed system of stored procedures should provide everything the application needs, including transactioning.
The application shouldn't need to know about the details of the schema and what the stored procedures are doing, and therefore should be able to just execute the stored procedures without thought to whether or not to use transactions.
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I think there are several factors that affect the choice how transactions should be used.
In my example I used two separate procedures that are executed in a sequence. If the execution as a whole should have ACID properties, the must be wrapped inside a common transaction. Basically this gives two options:
1. create a new stored procedure combining both calls thus leading to single call to backend
2. use transaction with a scope over two different SQL calls
In point 1, transaction problem is solved (in a simple case) but also the backend now knows (at least partly) the business logic (order of operations and the sequence). This may or may not be acceptable. The problem becomes more difficult if the procedures are not located in the same backend
In point 2, we would need a higher level transaction manager (such as classes in System.Transactions namespace or even self made mechanism). This adds extra 'overhead' to the programming but also it's possible to have more resources inside the same transactions. If this is needed, is again depending on the requirements of the system.
One good link that came in mind: http://blogs.msdn.com/diegumzone/archive/2006/08/14/699219.aspx[^]
The need to optimize rises from a bad design.
My articles[ ^]
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