TSQL - Add Column To All Tables in a Database [ Cursor Example]

Scenario:

Sometime we have requirement that add column in all the tables in Database. Today we have to add CreatedOn column in all the tables if it does not exist in table already.

Solution:

We will be using Cursor to perform this operation.
Please provide Column name and Data Type for these variables. In below example I am adding CreatedOn column with DateTime data type.

SET @COLUMN_NAME='ColumnNameYouWantToAdd'
SET @COLUMN_DATATYPE='DataTypeOfColumn'


------------------------------------------------Code---------------------------------------------------
USE TESTDB
GO
--Declare Variables
DECLARE @TableName VARCHAR(100)
DECLARE @TableSchema VARCHAR(100)
DECLARE @COLUMN_NAME VARCHAR(50)
SET @COLUMN_NAME='CreatedOn' --> Change Column Name according to your requirement
DECLARE @COLUMN_DATATYPE VARCHAR(50)
SET @COLUMN_DATATYPE='DateTime' --> Provide data type for column

--Declare Cursor
DECLARE CUR CURSOR FOR
  SELECT TABLE_SCHEMA,
         TABLE_NAME
  FROM   INFORMATION_SCHEMA.TABLES
  WHERE  TABLE_TYPE = 'BASE TABLE'
     
--OPEN CURSOR
OPEN CUR
--Fetch First Row
FETCH NEXT FROM CUR INTO @TableSchema,@TableName

--Loop
WHILE @@FETCH_STATUS = 0
  BEGIN

  DECLARE @SQL NVARCHAR(MAX)
  SET @SQL=NULL
  IF Not EXISTS ( Select 1 from INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME=@TableName AND COLUMN_NAME=@COLUMN_NAME)
  BEGIN
  SET @SQL='ALTER TABLE '+@TableSchema+'.'+@TableName +' ADD '+@COLUMN_NAME+ ''+@COLUMN_DATATYPE
    PRINT @SQL
    EXEC ( @SQL)
  END
   
  IF EXISTS ( Select 1 from INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME=@TableName AND COLUMN_NAME=@COLUMN_NAME)
  BEGIN
  Print 'Column Already exists in Table'
  END
      FETCH NEXT FROM CUR INTO @TableSchema,@TableName
  END

--Close and Deallocate Cursor
CLOSE CUR
DEALLOCATE CUR