Query (click) on layer with overlapping polygons gives error message

[havard.tveite@…]

I have a PostGIS layer with overlapping polygons. Querying by
clicking returns the expected result (info about the polygon
object and a map) when clicking on points where there is no
overlap between polygons.
When clicking on points where there is an overlap of polygons,
only information about one polygon plus a strange error message
is returned (no map, and no information about the rest of the
polygon objects):
"Content-type: text/html  msSearchDiskTree(): Unable to access file. Unable to
open spatial index for /home/www/mapserver/o-kart/../data/n5000/fylk-bal.qix. In
most cases you can safely ignore this message, otherwise check file names and
permissions."

For point layers, everyting seems to be working correctly (multiple
point objects are returned by the query when clicking close to many
points.
I checked an earlier 3.7 build, and it gives exactly the same error
message.

[sdlime]

Interesting bug. The error message itself is just what was the last error set by
the software so it doesn't tell us much except that it's bailing without
properly setting an error message. So, it may really help. It's not a query
error so I suspect but rather something in the template code. Could also be
something specific to PostGIS itself. My test query interface doesn't include
overlapping polygons but it does cover selecting multiple polygons with a single
point and I've seen no problems there. 

Any chance you could convert the PostGIS polygon layer to a polygon shapefile?
That would help me eliminate PostGIS as the culprit.

Steve

[havard.tveite@…]

I exported the polygon data from PostGIS to shape (pgsql2shp).
Substituting the resulting shape file for the PostGIS connection
gives the expected (correct) nquery behaviour, so according to
Steve Lime, this bug has probably something to do with the
PostGIS interface.

[mark@…]

This resulted from a change in PostgreSQL 7.4 that required cursors to be
explicitly closed at the end of transactions.  It was fixed in rev1.31.