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From: Mike Fowler on 28 Jun 2010 12:39 Robert Haas wrote: > On Mon, Jun 28, 2010 at 11:42 AM, Mike Rylander <mrylander(a)gmail.com> wrote: > >> You could do something like this (untested): >> >> CREATE OR REPLACE FUNCTION my_xml_is_valid ( x TEXT ) RETURNS BOOL AS $$ >> BEGIN >> PERFORM XMLPARSE( DOCUMENT x::XML ); >> RETURN TRUE; >> EXCEPTION WHEN OTHERS THEN >> RETURN FALSE; >> END; >> $$ LANGUAGE PLPGSQL; >> > > This might perform significantly worse, though: exception handling ain't cheap. > > It's not a bad workaround, but I think the OP has a point. > > Should the IS DOCUMENT predicate support this? At the moment you get the following: template1=# SELECT '<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>' IS DOCUMENT; ?column? ---------- t (1 row) template1=# SELECT '<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns' IS DOCUMENT; ERROR: invalid XML content LINE 1: SELECT '<towns><town>Bidford-on-Avon</town><town>Cwmbran</to... ^ DETAIL: Entity: line 1: parser error : expected '>' owns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns ^ Entity: line 1: parser error : chunk is not well balanced owns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns ^ I would've hoped the second would've returned 'f' rather than failing. I've had a glance at the XML/SQL standard and I don't see anything in the detail of the predicate (8.2) that would specifically prohibit us from changing this behavior, unless the common rule 'Parsing a string as an XML value' (10.16) must always be in force. I'm no standard expert, but IMHO this would be an acceptable change to improve usability. What do others think? Regards, -- Mike Fowler Registered Linux user: 379787 "I could be a genius if I just put my mind to it, and I, I could do anything, if only I could get 'round to it" -PULP 'Glory Days' -- Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
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