How to move the LOB data from one file group to other?

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We do not have a direct way to move the LOB data from one file group to other. Using ALTER TABLE and/or CREATE INDEX to support moving LOB data is unavailable till current version of SQL (SQL Server 2008).

 

Only way to move the LOB data is to

1. create new table in new file group

2. Move the data from existing table to new table.

3. Drop the existing table.

4. Change the name of new table to Old table.

Management studio has easy way to create script for all the above task.

1. In management studio Right click the table –>Design –>change the file group in properties windows (Click View—> properties window if you do not see properties window)

2. Generate Change Script.

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3. Script similar to following script is generated.

4. Copy the script and run in Query window.

 

/* To prevent any potential data loss issues, you should review this script in detail before running it outside the context of the database designer.*/

BEGIN TRANSACTION

SET QUOTED_IDENTIFIER ON

SET ARITHABORT ON

SET NUMERIC_ROUNDABORT OFF

SET CONCAT_NULL_YIELDS_NULL ON

SET ANSI_NULLS ON

SET ANSI_PADDING ON

SET ANSI_WARNINGS ON

COMMIT

BEGIN TRANSACTION

GO

CREATE TABLE dbo.Tmp_BLOB_TABLE

                (

                BLOBName varchar(100) NULL,

                BLOBData varbinary(MAX) NULL

                )  ON [PRIMARY]

                TEXTIMAGE_ON Lob2

GO

ALTER TABLE dbo.Tmp_BLOB_TABLE SET (LOCK_ESCALATION = TABLE)

GO

IF EXISTS(SELECT * FROM dbo.BLOB_TABLE)

                EXEC('INSERT INTO dbo.Tmp_BLOB_TABLE (BLOBName, BLOBData)

                                SELECT BLOBName, BLOBData FROM dbo.BLOB_TABLE WITH (HOLDLOCK TABLOCKX)')

GO

DROP TABLE dbo.BLOB_TABLE

GO

EXECUTE sp_rename N'dbo.Tmp_BLOB_TABLE', N'BLOB_TABLE', 'OBJECT'

GO

COMMIT

 

Thanks

Karthick P.K