DECLARE @dropIndexSql nvarchar(4000)
SET @dropIndexSql = N'DROP INDEX [Advertis].[AddUser]'
BEGIN TRY
   PRINT @dropIndexSql
   EXEC sp_executesql @dropIndexSql
END TRY
BEGIN CATCH
   Print ERROR_MESSAGE()
END CATCH
IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'Advertis' AND COLUMN_NAME = 'AddUser')
   BEGIN
      BEGIN TRY
         PRINT @dropIndexSql
         SET @dropIndexSql = N'ALTER TABLE [Advertis] ADD [AddUser] int'
         EXEC sp_executesql @dropIndexSql
      END TRY
      BEGIN CATCH
         Print ERROR_MESSAGE()
      END CATCH
   END
   ELSE
   BEGIN
      BEGIN TRY
         SET @dropIndexSql = N'ALTER TABLE [Advertis] ADD [AddUser-Temporary] int'
         PRINT @dropIndexSql
         EXEC sp_executesql @dropIndexSql
         SET @dropIndexSql = N'UPDATE [Advertis] SET [AddUser-Temporary]=AddUser'
         PRINT @dropIndexSql
         EXEC sp_executesql @dropIndexSql
         SET @dropIndexSql = N'ALTER TABLE [Advertis] DROP COLUMN [AddUser]'
         PRINT @dropIndexSql
         EXEC sp_executesql @dropIndexSql
         PRINT 'Renaming the field'
         EXEC sp_RENAME 'Advertis.AddUser-Temporary', 'AddUser' , 'COLUMN'
      END TRY
      BEGIN CATCH
         Print ERROR_MESSAGE()
      END CATCH
   END