declare
    object_exists exception;
    pragma exception_init (object_exists , -00955);
begin
	execute immediate 'ALTER TABLE CAJA ADD (
										TRANSACAO_ID NUMBER(15,0),
										TRANSACAOORIGINAL_ID NUMBER(15,0),
										DESCNUMDOC VARCHAR2(45 BYTE),
										DESCNUMDOC2 VARCHAR2(45 BYTE),
										DESCTIPODOC	VARCHAR2(15 BYTE),
										DESCTIPODOC2 VARCHAR2(15 BYTE),
										DESCTELEFONO VARCHAR2(15 BYTE)
											)';
    exception when object_exists then null;
end;