declare
    table_exists exception;
    pragma exception_init (table_exists , -00955);
begin
  execute immediate 
        'CREATE TABLE REGION_METROPOLITANA 
        (
          REGIONMETROPOLITANA_ID NUMBER(7,0) NOT NULL ENABLE,  
          DESCREGION VARCHAR2(100),
          ACTIVO NUMBER(1,0), 
          FECMODIF DATE, 
          USUARIO_ID NUMBER(7,0), 
          CONSTRAINT REGION_METROPOLITANA_PK PRIMARY KEY (REGIONMETROPOLITANA_ID) 
        ENABLE)';
    exception when table_exists then null;
end;