[mapserver-dev] help! strange preserving invalid query in mapobject

[Tamas Szekeres]

Hi,

Actually queryByAttributes doesn`t restore the filter to the previous
value. I consider this as a bug so don`t hesitate to file a ticket
with this issue.
You can workaround the problem by restoring the filter to a default state, like:

layer.setFilter(null);
layer.filteritem = null;


Some further notes:

It`s the caller`s responsibitity to avoid the passing invalid
parameters to the functions, therefore you should raise an error to
the user instead of calling queryByAttributes in this case.

You should avoid using the same mapObj instance in the subsequent
queries, mapscript objects cannot safely passed between multiple
threads. But you could anyway store a prototype mapObj in a session
object but you should call mapObj.clone() somewhere at the beginning
of the handler and operate on the clone afterwards.

Best regards,

Tamas



2008/6/6 BrainDrain <paulborodaev at gmail.com>:
>
> I use mapscript in c#, data from postgis, map file is correct. My web service
> produce map image with mapObj.draw() method, mapObj stored in session state
> object to prevent useless mapfile parsing every time calling web server. My
> web app has an attribute query widget, which can initiate invalid query
> string (filter) - sql where expression (just misprint for ex.). For ex. we
> have empty (zero length) query string "" for table street_axis. that will
> produce an an exception during layer.queryByAttributes(map, "", filter,
> mapscript.MS_MULTIPLE). After! this error occurred I have an exception in my
> web service (when requested by openlayers rich client js lib (by
> zoomming/panning map)). This is expected:
>  Message="msDrawMap(): Image handling error. Failed to draw layer named
> 'street_axis'.;prepare_database(): Query error. Error executing POSTGIS
> DECLARE (the actual query) statement: 'DECLARE mycursor BINARY CURSOR FOR
> SELECT
> \"name\"::text,asbinary(force_collection(force_2d(geom)),'NDR'),id::text
> from public.street_axis WHERE () and (geom && setSRID(
> 'BOX3D(240.340106037016 704.038663225639,418.96195656596
> 822.319350804203)'::BOX3D,find_srid('','public.street_axis','geom') ))'
> \n\nPostgresql reports the error as 'ERROR:  syntax error at or near
> \")\"\nLINE 1: ...)),'NDR'),id::text from public.street_axis WHERE () and
> (geo...\ bla bla bla. But what can I do to reset this invalid query in my
> map object??? remove it?
> I tried many ways right before calling map.draw() method (with or without
> catching query exception):
> 1) map.freeQuery(-1);
> 2) map.freeQuery for all layers;
> 3) turning on/off map.querymap.status;
> 4) map.drawQuery() instead of draw();
> 5) map.loadQuery with empty query (previously saved by 'clean' map);
> 6) PROCESSING "CLOSE_CONNECTION=DEFER" or without it (in map file);
> 7) opening/closing layers;
> 8) even !!! making new dummy valid query returning 0 records (something like
> "id<0") on catching exception
>  ... but nothing helped me!!!
> Only the way I can use now is parsing mapObj from scratch from my temporary
> saved map file? but i don't like it:).
> --
> View this message in context: http://www.nabble.com/help%21-strange-preserving-invalid-query-in-mapobject-tp17667367p17667367.html
> Sent from the Mapserver - Dev mailing list archive at Nabble.com.
>
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