The following bug has been logged online:
Bug reference: 5534
Logged by: Mike Fowler
Email address: mike(at)mlfowler(dot)com
PostgreSQL version: 9.0beta2
Operating system: Linux 2.6.31-14-generic #48-Ubuntu SMP
Description: IS DOCUMENT predicate errors instead of returning false
Details:
IS DOCUMENT should return false for a non-well formed document, and indeed
is coded to do such. However, the conversion to the xml type which happens
before the underlying xml_is_document function is even called fails and
exceptions out. I've mentioned this on -hackers with message ID
20100701172553(dot)w5vdy1xbocos8g40(at)www(dot)mlfowler(dot)com