I'm guessing this has never been used (at least with pyPgSQL, anyway), since it has a function listRequest defined thusly: def listRequest(self): # COALESCE may not be totally portable # it is shorthand for # CASE WHEN (first parameter) IS NOT NULL then (first parameter) ELSE (second parameter) END sql = """ SELECT groups.name, COALESCE(MAX(postings.article_index), 0), COALESCE(MIN(postings.article_index), 0), groups.flags FROM groups LEFT OUTER JOIN postings ON postings.group_id = groups.group_id GROUP BY groups.name, groups.flags ORDER BY groups.name """ return self.runQuery(sql) ... but PostgreSQL doesn't implement a COALESCE command. And my next guess would be that it's never been tested, either. Correct? If so, maybe it should be either be fixed or jettisoned, or at least relegated to the sandbox. - Steve.