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How to write text to a file with SQL Server

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The following is a tutorial on creating a stored procedure that will allow you to create a file in any directory and insert text into this newly created file.

In order for this to work you will need to authorise the running of system stored procedures with Object Linking and Embedding functionality (See OLE).

Authorisation is needed as the stored procedure we will create rely on the system SPs sp_OACreate and sp_OAMethod.

sp_OACreate: Creates an instance of an OLE object.

sp_OAMethod: Calls a method of an OLE object.

NOTE: By default, SQL Server blocks access to OLE Automation stored procedures by turning the components off as part of the security configuration for the server.

Run the script below to grant authorisation.

--AUTHORIZE SYSTEM STORED PROCEDURES
sp_configure 'show advanced options'
	,1;
GO

RECONFIGURE;
GO

sp_configure 'Ole Automation Procedures'
	,1;
GO

RECONFIGURE;
GO

--AUTHORIZED

 
Next we will create the stored procedure WriteToFile. Substitute the DatabaseName with the database you will be using.

--CREATE STORED PROCEDURE
/*
CHANGE:
DATABASE NAME: DatabaseName 
 */
USE "DatabaseName";
GO

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

IF OBJECT_ID('[dbo].[WriteToFile]', 'P') IS NOT NULL
	DROP PROCEDURE [WriteToFile];
GO

CREATE PROCEDURE [dbo].[WriteToFile] @File VARCHAR(255)
	,@Text VARCHAR(MAX)
	WITH EXECUTE AS CALLER
AS
BEGIN
	DECLARE @OLE INT
	DECLARE @FileID INT

	EXECUTE sp_OACreate 'Scripting.FileSystemObject'
		,@OLE OUT

	EXECUTE sp_OAMethod @OLE
		,'OpenTextFile'
		,@FileID OUT
		,@File
		,8
		,1

	EXECUTE sp_OAMethod @FileID
		,'WriteLine'
		,NULL
		,@Text

	EXECUTE sp_OADestroy @FileID

	EXECUTE sp_OADestroy @OLE
END;

 
Below is an example using the WriteToFile stored procedure.

--WRITE TO FILE EXAMPLE
/*
CHANGE:
DATABASE NAME: DatabaseName 
 */
USE "DatabaseName";
GO

DECLARE @Path VARCHAR(255)
DECLARE @Txt VARCHAR(MAX)

--NOTE: THE LOG FILE WILL BE CREATED IF IT DOES NOT ALREADY EXIST
SET @PATH = 'C:\temp\WriteToFileExampleLog.txt'
SET @Txt = 'Hello World'

EXEC [DatabaseName].[dbo].[WriteToFile] @Path
	,@Txt;

 

Using the same stored procedure here’s an example writing a table to the file using concatenation and a loop. This process works by taking the table row by row and writing the concatenated value to the file. There are easier ways to achieve this however, i.e. utilising the export functionality built into SSMS and saving this as a package to be run as a job.

--STORED PROCEDURE CREATED
--WRITE TABLE TO FILE EXAMPLE
DECLARE @Path VARCHAR(255)
DECLARE @Txt VARCHAR(MAX)
DECLARE @loopId AS INT
DECLARE @maxId AS INT
DECLARE @TempCustomer TABLE (
	ID_column INT IDENTITY PRIMARY KEY
	,FirstName NVARCHAR(100)
	);

--NOTE: THE LOG FILE WILL BE CREATED IF IT DOES NOT ALREADY EXIST
SET @PATH = 'C:\temp\WriteToFileExampleLog.txt'

INSERT INTO @tempCustomer (FirstName)
VALUES ('Paul')
	,('Jim')
	,('John')

SET @loopId = 1
SET @maxId = (
		SELECT MAX(ID_column)
		FROM @TempCustomer
		)

WHILE @loopId <= @maxId
BEGIN
	SELECT @Txt = CONVERT(VARCHAR(10), ID_column) + ', ' + FirstName
	FROM @TempCustomer
	WHERE ID_column = @loopId

	PRINT @Txt

	EXEC [TEST_DB].[dbo].[WriteToFile] @Path
		,@Txt;

	SET @loopId = @loopId + 1
END