-- FUNCTION: public.isdate(character varying)

-- DROP FUNCTION public.isdate(character varying);

CREATE OR REPLACE FUNCTION public.isdate(

    datestr character varying)

    RETURNS boolean

    LANGUAGE 'plpgsql'

    COST 100

    VOLATILE

AS $BODY$

BEGIN

IF (dateStr IS NULL) THEN

     RETURN FALSE;

END IF;

     PERFORM dateStr::timestamp;

     RETURN TRUE;

EXCEPTION

     WHEN others THEN

     RETURN FALSE;

END;

$BODY$;

 -- FUNCTION: public.isnumeric(character varying)

 -- DROP FUNCTION public.isnumeric(character varying);

 CREATE OR REPLACE FUNCTION public.isnumeric(

     txtstr character varying)

     RETURNS boolean

     LANGUAGE 'plpgsql'

     COST 100

     VOLATILE

 AS $BODY$

 BEGIN 

 RETURN txtStr ~ '^([0-9]+[.]?[0-9]*|[.][0-9]+)$'; 

 END;

 $BODY$;