USE database not allowed in a procedure

Question

I currently use a microsoft sql script to defrag indexes above a critical value, code and link below defrag. This works fine when I simply execute the code but now I would like to create a stored procedure and a job to automate the task. My problem is that the code needs to have 'USE ' at the start which you can not have in a SP. How can I modify the script to overcome this?

USE mydbname

-- Declare variables
SET NOCOUNT ON;
DECLARE @tablename varchar(255);
DECLARE @execstr   varchar(400);
DECLARE @objectid  int;
DECLARE @indexid   int;
DECLARE @frag      decimal;
DECLARE @maxfrag   decimal;

-- Decide on the maximum fragmentation to allow for.
SELECT @maxfrag = 30.0;

-- Declare a cursor.
DECLARE tables CURSOR FOR
   SELECT TABLE_SCHEMA + '.' + TABLE_NAME
   FROM INFORMATION_SCHEMA.TABLES
   WHERE TABLE_TYPE = 'BASE TABLE';

-- Create the table.
CREATE TABLE #fraglist (
   ObjectName char(255),
   ObjectId int,
   IndexName char(255),
   IndexId int,
   Lvl int,
   CountPages int,
   CountRows int,
   MinRecSize int,
   MaxRecSize int,
   AvgRecSize int,
   ForRecCount int,
   Extents int,
   ExtentSwitches int,
   AvgFreeBytes int,
   AvgPageDensity int,
   ScanDensity decimal,
   BestCount int,
   ActualCount int,
   LogicalFrag decimal,
   ExtentFrag decimal);

-- Open the cursor.
OPEN tables;

-- Loop through all the tables in the database.
FETCH NEXT
   FROM tables
   INTO @tablename;

WHILE @@FETCH_STATUS = 0
BEGIN
-- Do the showcontig of all indexes of the table
   INSERT INTO #fraglist 
   EXEC ('DBCC SHOWCONTIG (''' + @tablename + ''') 
      WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS');
   FETCH NEXT
      FROM tables
      INTO @tablename;
END;

-- Close and deallocate the cursor.
CLOSE tables;
DEALLOCATE tables;

-- Declare the cursor for the list of indexes to be defragged.
DECLARE indexes CURSOR FOR
   SELECT ObjectName, ObjectId, IndexId, LogicalFrag
   FROM #fraglist
   WHERE LogicalFrag >= @maxfrag
      AND INDEXPROPERTY (ObjectId, IndexName, 'IndexDepth') > 0;

-- Open the cursor.
OPEN indexes;

-- Loop through the indexes.
FETCH NEXT
   FROM indexes
   INTO @tablename, @objectid, @indexid, @frag;

WHILE @@FETCH_STATUS = 0
BEGIN
   PRINT 'Executing DBCC INDEXDEFRAG (0, ' + RTRIM(@tablename) + ',
      ' + RTRIM(@indexid) + ') - fragmentation currently '
       + RTRIM(CONVERT(varchar(15),@frag)) + '%';
   SELECT @execstr = 'DBCC INDEXDEFRAG (0, ' + RTRIM(@objectid) + ',
       ' + RTRIM(@indexid) + ')';
   EXEC (@execstr);

   FETCH NEXT
      FROM indexes
      INTO @tablename, @objectid, @indexid, @frag;
END;

-- Close and deallocate the cursor.
CLOSE indexes;
DEALLOCATE indexes;

-- Delete the temporary table.
DROP TABLE #fraglist;
GO

Answer 1

Don't reinvent the wheel... Ola Hallegren script is pretty much industry standard...

https://ola.hallengren.com/sql-server-index-and-statistics-maintenance.html

Also, you don't have to use USE. Just call the object using the 3 part naming convention. <DatabaseName>.<SchemaName>.<ObjectName>

Answer 2

USE is a SSMS command, not a SQL command. You can have the USE statement at the top, then delimit it with a GO, after which create the procedure. This will create the stored procedure in the context of the desired database. If you need the sproc in multiple databases, just change the USE statement at the top, and run as many times as you want for each DB.

USE mydbname

GO
Create Procedure DefragDB AS Begin
-- Declare variables
SET NOCOUNT ON;
DECLARE @tablename varchar(255);
DECLARE @execstr   varchar(400);
DECLARE @objectid  int;
DECLARE @indexid   int;
DECLARE @frag      decimal;
DECLARE @maxfrag   decimal;

-- Decide on the maximum fragmentation to allow for.
SELECT @maxfrag = 30.0;

-- Declare a cursor.
DECLARE tables CURSOR FOR
   SELECT TABLE_SCHEMA + '.' + TABLE_NAME
   FROM INFORMATION_SCHEMA.TABLES
   WHERE TABLE_TYPE = 'BASE TABLE';

-- Create the table.
CREATE TABLE #fraglist (
   ObjectName char(255),
   ObjectId int,
   IndexName char(255),
   IndexId int,
   Lvl int,
   CountPages int,
   CountRows int,
   MinRecSize int,
   MaxRecSize int,
   AvgRecSize int,
   ForRecCount int,
   Extents int,
   ExtentSwitches int,
   AvgFreeBytes int,
   AvgPageDensity int,
   ScanDensity decimal,
   BestCount int,
   ActualCount int,
   LogicalFrag decimal,
   ExtentFrag decimal);

-- Open the cursor.
OPEN tables;

-- Loop through all the tables in the database.
FETCH NEXT
   FROM tables
   INTO @tablename;

WHILE @@FETCH_STATUS = 0
BEGIN
-- Do the showcontig of all indexes of the table
   INSERT INTO #fraglist 
   EXEC ('DBCC SHOWCONTIG (''' + @tablename + ''') 
      WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS');
   FETCH NEXT
      FROM tables
      INTO @tablename;
END;

-- Close and deallocate the cursor.
CLOSE tables;
DEALLOCATE tables;

-- Declare the cursor for the list of indexes to be defragged.
DECLARE indexes CURSOR FOR
   SELECT ObjectName, ObjectId, IndexId, LogicalFrag
   FROM #fraglist
   WHERE LogicalFrag >= @maxfrag
      AND INDEXPROPERTY (ObjectId, IndexName, 'IndexDepth') > 0;

-- Open the cursor.
OPEN indexes;

-- Loop through the indexes.
FETCH NEXT
   FROM indexes
   INTO @tablename, @objectid, @indexid, @frag;

WHILE @@FETCH_STATUS = 0
BEGIN
   PRINT 'Executing DBCC INDEXDEFRAG (0, ' + RTRIM(@tablename) + ',
      ' + RTRIM(@indexid) + ') - fragmentation currently '
       + RTRIM(CONVERT(varchar(15),@frag)) + '%';
   SELECT @execstr = 'DBCC INDEXDEFRAG (0, ' + RTRIM(@objectid) + ',
       ' + RTRIM(@indexid) + ')';
   EXEC (@execstr);

   FETCH NEXT
      FROM indexes
      INTO @tablename, @objectid, @indexid, @frag;
END;

-- Close and deallocate the cursor.
CLOSE indexes;
DEALLOCATE indexes;

-- Delete the temporary table.
DROP TABLE #fraglist;
END