IF COL_LENGTH('[dbo].[clitelefone]', 'padrao') IS NULL
BEGIN
  ALTER TABLE [dbo].[clitelefone] ADD padrao CHAR(1) NULL;
END

IF COL_LENGTH('[dbo].[clitelefone]', 'operadora') IS NULL
BEGIN
  ALTER TABLE [dbo].[clitelefone] ADD operadora NUMERIC(5,0) NULL;
END

IF COL_LENGTH('[dbo].[clitelefone]', 'ramal') IS NULL
BEGIN
  ALTER TABLE [dbo].[clitelefone] ADD ramal VARCHAR(5) NULL;
END