IF NOT EXISTS (SELECT * FROM SYS.COLUMNS WHERE NAME = 'FLAG_COMIS_QTDE' AND OBJECT_ID = OBJECT_ID('EST_PROD_TBL_COMIS'))
begin
ALTER TABLE dbo.EST_PROD_TBL_COMIS ADD
	FLAG_COMIS_QTDE int NOT NULL CONSTRAINT DF_EST_PROD_TBL_COMIS_FLAG_COMIS_QTDE DEFAULT 0
end