Stored Procedure Automatically Calling Another Stored Procedure? - sql

I'm working on modifying some code around and I noticed that when I go to execute a stored procedure, lets call it 'yyyyyyyyy_sproc' I get an error saying that 'xxxxxxxxxxx_sproc' doesn't exist (saying that there are two different names).
I went into the code of sproc 'yyyyyyyyyy_sproc' and didn't see anywhere where 'xxxxxxxxx_sproc' was being used. My question is, is there a process in SSMS that automatically links two sprocs together? As using EXEC 'yyyyyyyyy_sproc' would therefor trigger an error if there was an issue with 'xxxxxxxxxxxxx_sproc'?

Related

Using MSDB stored procedures in application's database stored procedure

This seems like it would be trivial, but I have not been able to come up with a solution to this small problem.
I am attempting to create a stored procedure in my application's database. This stored procedure just executes a job that has been set up in the SSMS on the same server (seemed to be the only way to programmatically execute these jobs).
The simple code is shown below:
USE ApplicationsDatabase
GO
CREATE PROCEDURE [dbo].[procedure]
AS
BEGIN
EXEC dbo.sp_start_job N'Nightly Download'
END
When ran as is, the procedure technically gets created but cannot be executed due to it not being able to find the 'sp_start_job' since it is using the ApplicationsDatabase. If I try to create the procedure again (after deleting previously created) but updating the USE to MSDB, it tries to add it to that system database for which I do not have permissions to do. Finally, I attempted to keep the original create statement but added the USE MSDB within the procedure (just to use the 'sp_start_job' procedure), but it would error saying USE statements cannot be placed within procedures.
After pondering on the issue for a little (I'm obviously no SQL database expert), I could not come up with a solution and decided to solicit the advice of my peers. Any help would be greatly appreciated, thanks!
You will have to fully qualify the path to the procedure. Of course, you can only execute this is the application has permissions.
Try this:
USE ApplicationsDatabase
GO
CREATE PROCEDURE [dbo].[procedure]
AS
BEGIN
EXEC msdb.dbo.sp_start_job N'Nightly Download'
END

Calling a series of stored procedures sequentially SQL

Is it possible (using only T-SQL no C# code) to write a stored procedure to execute a series of other stored procedures without passing them any parameters?
What I mean is that, for example, when I want to update a row in a table and that table has a lot of columns which are all required, I want to run the first stored procedure to check if the ID exists or not, if yes then I want to call the update stored procedure, pass the ID but (using the window that SQL Server manager shows after executing each stored procedure) get the rest of the values from the user.
When I'm using the EXEC command, I need to pass all the parameters, but is there any other way to call the stored procedure without passing those parameter? (easy to do in C# or VB, I mean just using SQL syntax)
I think you are asking "can you prompt for user input in a sql script?". No not really.
You could actually do it with seriously hack-laden calls to the Windows API. And it would almost certainly have serious security problems.
But just don't do this. Write a program in C#, VB, Access, Powerscript, Python or whatever makes you happy. Use an tool appropriate to the task.
-- ADDED
Just so you know how ugly this would be. Imagine using the Flash component as an ActiveX object and using Flash to collect input from the user -- now you are talking about the kind of hacking it would be. Writing CLR procs, etc. would be just as big of a hack.
You should be cringing right now. But it gets worse, if the TSQL is running on the sql server, it would likely prompt or crash on the the server console instead of running on your workstation. You should definitely be cringing buy now.
If you are coming from Oracle Accept, the equivalent in just not available in TSQL -- nor should it be, and may it never be.
Right after reading your comment now I can understand what you are trying to do. You want to make a call to procedure and then ask End User to pass values for Parameters.
This is a very very badddddddddddddddddddd approach, specially since you have mentioned you will be making changes to database with this SP.
You should get all the values from your End Users before you make a call to your database(execute procedure), Only then make a call to database you Open a transaction and Commit it or RollBack as soon as possible and get out of there. as it will be holding locks on your resources.
Imagine you make a call to database (execute sp) , sp goes ahead and opens a transaction and now wait for End user to pass values, and your end user decides to go away for a cig, this will leave your resources locked and you will have to go in and kill the process yourself in order to let other user to go and use database/rows.
Solution
At application level (C#,VB) get all the values from End users and only when you have all the required information, only then pass these values to sp , execute it and get out of there asap.
You can specify the parameters by prefixing the name of the parameter with the # sign. For example, you can call an SP like this:
EXEC MyProc #Param1='This is a test'
But, if you are asking if you can get away with NOT providing required parameters, the answer is NO. Required is required. You can make them optional by providing a default value in the declaration of the SP. Then you can either not pass the value or call it like this:
EXEC MyProc #Param1=DEFAULT
--OR
EXEC MyProc DEFAULT

Running synchronous commands to between two sql servers

I'm running a stored procedure on server1 from my application. The stored procedure does a bunch of stuff and populate a table on server2 with the result from the procedure.
I'm using linked server to accomplish this.
When the stored procedure is done running the application continues and tries to do some manipulation of the result from the stored procedure.
My problem is that the results from the stored procedure has not been completely inserted into the tables yet, so the manipulation of the tables fails.
So my question is. Is it possible to ensure the insert into on the linked server is done synchronous? I would like to have the stored procedure not return until the tables on the linked server actually is done.
You can use an output parameter of the first procedure. When the table is create on the second server the output parameter value will be return to your application and indicates the operation is ready.
If the things are difficult then this you can try setting a different isolation level of your store procedure:
http://msdn.microsoft.com/en-us/library/ms173763.aspx
I found the reason for this strange behavior. There was a line of code in my stored procedure added during debug that did a select on a temporary mem table before the data in the same table was written to the linked server.
When the select statement was run, the control was given back to my application and at the same time the stored procedure continued running. I guess the stored procedure was running synchronously from the start.

Stored Procedure passing control back too quickily - VB6

I have a stored procedure that is updating a very large table (with over 100 million records). The stored procedure is updating records in this table.
The steps are as follows:
Store record IDs to be updated in a recordset (not all records will be updated - only about 20000)
Loop through the recordset and call the stored procedure for each record ID in the recordset
Each time the stored procedure has finished (for each record in the recordset mentioned in part 1), update a flag in a table to say that the update completed.
I am finding some strange behaviour. It appears that the stored procedure is passing control back to VB6 before it has completed its updates and is continuing processing the next record. The stored procedure is then timing out later on (on another record ID). Therefore there are flags that say updated (step 3), even though the stored procedure has not run (because it timed out). Is this normal behaviour i.e. for the stored procedure to pass control back to VB6 before it has finished the work?
I have Googled this and I have discovered that it could be because of the way the stored procedure is optimised by SQL Server. I would expect control only to be passed back to VB6 after the updates have completed. Is this not the case?
Please note that I realise there may be better ways of approaching this. My question specifically relates to SQL Server passing control back to VB6 before it has finished the work (update).
The following article proved to be the solution to this problem: http://weblogs.sqlteam.com/dang/archive/2007/10/20/Use-Caution-with-Explicit-Transactions-in-Stored-Procedures.aspx. It appears that the following behaviour was happening:
1) Record 1. Run stored procedure and create transaction. Timeout on SQL Command object occurrs.
2) Record 2. Run stored procedure successfully. Return constrol to VB6 to update flag in database.
3) Record 3. Run stored procedure successfully. Return constrol to VB6 to update flag in database.
4) Record 4. Run stored procedure successfully. Return constrol to VB6 to update flag in database.
5) Program ends. Stored procedure rolls back transaction (transaction now encompasses records 1-4). Therefore records 1-4 are not deleted.
Can you...
run the code in sql management studio and see what happens and report back? if so i will update this answer as that will help us understand if its the code / connection or sql.
other things to investigate, given we dont not what cases you have tested for...
use the same code path in ur vb application and change only the sql in the stored procedure to something very simple but has the same signature as far as what its doing (ie/ basica reading if there is reading, basic deleting if there is deleting, and same for updating and adding) to see what happens.
Also, some other thoughts...
if you are using MSSQL, it's as simple as someone leaving a query window open and it ties up the database. This is easily tested. I've had the same trouble before. I've run stored procedures before that had no timeout, that normally would run immediately but would sit overnight and not run. Only to realize another person left their query window open. Close their window and poof it finally runs. Check this out, it could be a table lock. Whether it be the application doing it, or it is being done by another user making queries to the DB. Check to make sure your application is closing connections to the DB each time their being used.

How to troubleshoot a stored procedure?

what is the best way of troubleshoot a stored procedure in SQL Server, i mean from where do you start etc..?
Test each SELECT statements (if any) outside of your stored procedure to see whether it returns the expected results;
Make INSERT and UPDATE statements as simple as possible;
Try to test Inserts and Updates outside of your SP so that you can check it gives the expected results;
Use the debugger provided with SSMS Express 2008.
Visual Studio 2008 / 2010 has a debug facility. Simply connect to to your SQL Server instance in 'Server Explorer' and browse to your stored procedure.
Visual Studio 'Test Edition' also can generate Unit Tests around your stored procedures.
Troubleshooting a complex stored proc is far more than just determining if you can get it to run or not and finding the step which won't run. What is most critical is whether it actually returns the corect results or performs the correct actions.
There are two kinds of stored procs that need extensive abilites to troublshoot. First the the proc which creates dynamic SQL. I never create one of these without an input parameter of #debug. When this parameter is set, I have the proc print the SQl statment as it would have run and not run it. Almost everytime, this leads you right away to the problem as you can then see the syntax error in the generated SQL code. You also can run this sql code to see if it is returning the records you expect.
Now with complex procs that have many steps that affect data, I always use an #test input parameter. There are two things I do with the #test parameter, first I make it rollback the actions so that a mistake in development won't mess up the data. Second, I have it display the data before it rollsback to see what the results would have been. (These actually appear in the reverse order in the proc; I just think of them in this order.)
Now I can see what would have gone into the table or been deleted from the tables without affecting the data permananently. Sometimes, I might start with a select of the data as it was before any actions and then compare it to a select run afterwards.
Finally, I often want to log actions of a complex proc and see exactly what steps happened. I don't want those logs to get rolled back if the proc hits an error, so I set up a table variable for the logging information I want at the start of the proc. After each step (or after an error depending on what I want to log), I insert to this table variable. After the rollback or commit statement, I select the results of the table variable or use those results to log to a permanent logging table. This can be especially nice if you are using dynamic SQL because you can log the SQL that was run and then when something strange fails on prod, you have a record of which statement was run when it failed. You do this in a table variable because those do not go out of scope in a rollback.
In SSMS, you can simply start by opening the proc., and clicking on the check mark button (Parse) next to the Execute button on the menu bar. It reports any errors it finds.
If there are no errors there and you're stored procedure is harmless to run (you're not inserting into tables, just creating a temp table for example), then comment out the CREATE PROCEDURE x (or ALTER PROCEDURE x) and declare all the parameters by copying that part, then define them with valid values. Then run it to see what happens.
Maybe this is simple, but it's a place to start.