308
votes

I have a SQL script that has to be run every time a client executes the "database management" functionality. The script includes creating stored procedures on the client database. Some of these clients might already have the stored procedure upon running the script, and some may not. I need to have the missing stored procedures added to the client database, but it doesn't matter how much I try to bend T-SQL syntax, I get

CREATE/ALTER PROCEDURE' must be the first statement in a query batch

I've read that dropping before creating works, but I don't like doing it that way.

IF EXISTS (SELECT * FROM sys.objects WHERE type = 'P' AND name = 'MyProc')
DROP PROCEDURE MyProc
GO

CREATE PROCEDURE MyProc
...

How can I add check for the existence of a stored procedure and create it if it doesn't exist but alter it if it does exist?

16
no it doesn't work, because that creates a stored procedure which is allegedly not what you want. from what we can see, it doesn't drop it after its done, either, so it's definitely stored in all aspects of the term. it is not irrelevant why you need a non-stored procedureDavid Hedlund
What do you mean by 'non-stored' procedure? All your sample does is recreate a stored procedure; what does this have to do with your question?AakashM
Ok, there we go. The thing is, I have a HUGE SQL script which many clients use and has to be ran thoroughly every time a client executes the "database management" functionality that our software provides. So some of these clients might already have the procedure stored upon running the script, and some may not. I know this is stupid, I don't actually need this procedure to remain unstored, I can just check if it exists and create it if it doesn't. However, it doesn't matter how much I try to bend T-SQL syntax, there's always an error.The Shaper
Every time they run the script, it will try to create the procedure again (unfortunatelly, it everything has to be scripted in the same .sql file including the create procedure call). IF NOT EXISTS THEN CREATE doesn't work due to syntax limitations. What can I do?The Shaper

16 Answers

226
votes

You can run procedural code anywhere you are able to run a query.

Just copy everything after AS:

BEGIN
    DECLARE @myvar INT
    SELECT  *
    FROM    mytable
    WHERE   @myvar ...
END

This code does exactly same things a stored proc would do, but is not stored on the database side.

That's much like what is called anonymous procedure in PL/SQL.

Update:

Your question title is a little bit confusing.

If you only need to create a procedure if it not exists, then your code is just fine.

Here's what SSMS outputs in the create script:

IF EXISTS ( SELECT  *
            FROM    sys.objects
            WHERE   object_id = OBJECT_ID(N'myproc')
                    AND type IN ( N'P', N'PC' ) ) 
DROP …
CREATE …

Update:

Example of how to do it when including the schema:

IF EXISTS ( SELECT * 
            FROM   sysobjects 
            WHERE  id = object_id(N'[dbo].[MyProc]') 
                   and OBJECTPROPERTY(id, N'IsProcedure') = 1 )
BEGIN
    DROP PROCEDURE [dbo].[MyProc]
END

In the example above, dbo is the schema.

Update:

In SQL Server 2016+, you can just do

CREATE OR ALTER PROCEDURE dbo.MyProc

479
votes

I realize this has already been marked as answered, but we used to do it like this:

IF NOT EXISTS (SELECT * FROM sys.objects WHERE type = 'P' AND OBJECT_ID = OBJECT_ID('dbo.MyProc'))
   exec('CREATE PROCEDURE [dbo].[MyProc] AS BEGIN SET NOCOUNT ON; END')
GO

ALTER PROCEDURE [dbo].[MyProc] 
AS
  ....

Just to avoid dropping the procedure.

133
votes

If you're looking for the simplest way to check for a database object's existence before removing it, here's one way (example uses a SPROC, just like your example above but could be modified for tables, indexes, etc...):

IF (OBJECT_ID('MyProcedure') IS NOT NULL)
  DROP PROCEDURE MyProcedure
GO

This is quick and elegant, but you need to make sure you have unique object names across all object types since it does not take that into account.

I Hope this helps!

42
votes

I know you want to "alter a procedure if it exists and create it if it does not exist" but I believe it's simpler to just always drop the procedure and then re-create it. Here's how to drop the procedure only if it already exists:

IF OBJECT_ID('MyProcedure', 'P') IS NOT NULL
    DROP PROCEDURE MyProcedure
GO

The second parameter tells OBJECT_ID to only look for objects with object_type = 'P', which are stored procedures:

AF = Aggregate function (CLR)

C = CHECK constraint

D = DEFAULT (constraint or stand-alone)

F = FOREIGN KEY constraint

FN = SQL scalar function

FS = Assembly (CLR) scalar-function

FT = Assembly (CLR) table-valued function

IF = SQL inline table-valued function

IT = Internal table

P = SQL Stored Procedure

PC = Assembly (CLR) stored-procedure

PG = Plan guide

PK = PRIMARY KEY constraint

R = Rule (old-style, stand-alone)

RF = Replication-filter-procedure

S = System base table

SN = Synonym

SO = Sequence object

TF = SQL table-valued-function

TR = Trigger

You can get the full list of options via:

SELECT name 
FROM master..spt_values
WHERE type = 'O9T'
29
votes

As of SQL SERVER 2016 you can use the new DROP PROCEDURE IF EXISTS.
DROP { PROC | PROCEDURE } [ IF EXISTS ] { [ schema_name. ] procedure } [ ,...n ]

Reference : https://msdn.microsoft.com/en-us/library/ms174969.aspx

26
votes

I know it is a very old post, but since this appears in the top search results hence adding the latest update for those using SQL Server 2016 SP1 -

create or alter procedure procTest
as
begin
 print (1)
end;
go

This creates a Stored Procedure if does not already exist, but alters it if exists.

Reference

15
votes

DROP IF EXISTS is a new feature of SQL Server 2016

https://blogs.msdn.microsoft.com/sqlserverstorageengine/2015/11/03/drop-if-exists-new-thing-in-sql-server-2016/

DROP  PROCEDURE IF EXISTS dbo.[procname]
8
votes

I had the same error. I know this thread is pretty much dead already but I want to set another option besides "anonymous procedure".

I solved it like this:

  1. Check if the stored procedure exist:

    IF NOT EXISTS (SELECT * FROM sysobjects WHERE name='my_procedure') BEGIN
        print 'exists'  -- or watever you want
    END ELSE BEGIN
        print 'doesn''texists'   -- or watever you want
    END
    
  2. However the "CREATE/ALTER PROCEDURE' must be the first statement in a query batch" is still there. I solved it like this:

    SET ANSI_NULLS ON
    GO
    SET QUOTED_IDENTIFIER ON
    GO
    
    CREATE -- view procedure function or anything you want ...
    
  3. I end up with this code:

    IF EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID('my_procedure'))
    BEGIN
        DROP PROCEDURE my_procedure
    END
    
    SET ANSI_NULLS ON
    GO
    SET QUOTED_IDENTIFIER ON
    GO
    
    CREATE PROCEDURE [dbo].my_procedure ...
    
6
votes

Here's a method and some reasoning behind using it this way. It isn't as pretty to edit the stored proc but there are pros and cons...

UPDATE: You can also wrap this entire call in a TRANSACTION. Including many stored procedures in a single transaction which can all commit or all rollback. Another advantage of wrapping in a transaction is the stored procedure always exists for other SQL connections as long as they do not use the READ UNCOMMITTED transaction isolation level!

1) To avoid alters just as a process decision. Our processes are to always IF EXISTS DROP THEN CREATE. If you do the same pattern of assuming the new PROC is the desired proc, catering for alters is a bit harder because you would have an IF EXISTS ALTER ELSE CREATE.

2) You have to put CREATE/ALTER as the first call in a batch so you can't wrap a sequence of procedure updates in a transaction outside dynamic SQL. Basically if you want to run a whole stack of procedure updates or roll them all back without restoring a DB backup, this is a way to do everything in a single batch.

IF NOT EXISTS (select ss.name as SchemaName, sp.name as StoredProc 
    from sys.procedures sp
    join sys.schemas ss on sp.schema_id = ss.schema_id
    where ss.name = 'dbo' and sp.name = 'MyStoredProc')
BEGIN
    DECLARE @sql NVARCHAR(MAX)

    -- Not so aesthetically pleasing part. The actual proc definition is stored
    -- in our variable and then executed.
    SELECT @sql = 'CREATE PROCEDURE [dbo].[MyStoredProc]
(
@MyParam int
)
AS
SELECT @MyParam'
    EXEC sp_executesql @sql
END
5
votes

In Sql server 2008 onwards, you can use "INFORMATION_SCHEMA.ROUTINES"

IF EXISTS (SELECT 1 FROM INFORMATION_SCHEMA.ROUTINES 
  WHERE ROUTINE_NAME = 'MySP'
        AND ROUTINE_TYPE = 'PROCEDURE') 
3
votes

**The simplest way to drop and recreate a stored proc in T-Sql is **

Use DatabaseName
go
If Object_Id('schema.storedprocname') is not null
begin
   drop procedure schema.storedprocname
end
go

create procedure schema.storedprocname
as

begin
end
3
votes

Here is the script that I use. With it, I avoid unnecessarily dropping and recreating the stored procs.

IF NOT EXISTS (
    SELECT *
    FROM sys.objects
    WHERE object_id = OBJECT_ID(N'[dbo].[uspMyProcedure]')
    )
BEGIN
  EXEC sp_executesql N'CREATE PROCEDURE [dbo].[uspMyProcedure] AS select 1'
END
GO

ALTER PROCEDURE [dbo].[uspMyProcedure] 
    @variable1 INTEGER  
AS
BEGIN
   -- Stored procedure logic
END
1
votes

why don't you go the simple way like

    IF EXISTS(SELECT * FROM sys.procedures WHERE NAME LIKE 'uspBlackListGetAll')
    BEGIN
         DROP PROCEDURE uspBlackListGetAll
    END
    GO

    CREATE Procedure uspBlackListGetAll

..........

0
votes

In addition to the answer from @Geoff I've created a simple tool which generates a SQL-file which statements for Stored Procedures, Views, Functions and Triggers.

See MyDbUtils @ CodePlex. enter image description here

0
votes

I wonder! Why i don't write the whole query like

GO
create procedure [dbo].[spAddNewClass] @ClassName varchar(20),@ClassFee int
as
begin
insert into tblClass values (@ClassName,@ClassFee)
end

GO
create procedure [dbo].[spAddNewSection] @SectionName varchar(20),@ClassID       int
as
begin
insert into tblSection values(@SectionName,@ClassID)
end

Go
create procedure test
as
begin 
select * from tblstudent
end

i already know that first two procedures are already exist sql will run the query will give the error of first two procedures but still it will create the last procedure SQl is itself taking care of what is already exist this is what i always do to all my clients!

-2
votes

CREATE Procedure IF NOT EXISTS 'Your proc-name' () BEGIN ... END