declare
    column_exists exception;
    pragma exception_init (column_exists , -01430);
begin
    execute immediate 'ALTER TABLE RUTA ADD (INDRUTAINTERNACIONAL NUMBER(1,0) DEFAULT 0 NOT NULL ENABLE)';
    exception when column_exists then null;
end;
/

-- Placeholder
declare
    column_exists exception;
    pragma exception_init (column_exists , -01430);
begin
    execute immediate 'ALTER TABLE CONDUCTOR ADD (NACIONALIDAD VARCHAR2(30 BYTE))';
    exception when column_exists then null;
end;
/

-- Placeholder
declare
    column_exists exception;
    pragma exception_init (column_exists , -01430);
begin
    execute immediate 'ALTER TABLE BOLETO ADD (NACIONALIDAD VARCHAR2(30 BYTE))';
    execute immediate 'ALTER TABLE BOLETO ADD (SEXO VARCHAR2(1 BYTE))';
    exception when column_exists then null;
end;
/

-- Placeholder
declare
    column_exists exception;
    pragma exception_init (column_exists , -01430);
begin
    execute immediate 'ALTER TABLE CAJA ADD (NACIONALIDAD VARCHAR2(30 BYTE))';
    execute immediate 'ALTER TABLE CAJA ADD (SEXO VARCHAR2(1 BYTE))';
    exception when column_exists then null;
end;