Folks,
I've created a bunch of spatial indexes on my DB2, but still the showing of maps is rather slow: should I re-register the spatial columns, re-deploy GeoServer or do something else to make them work ?
Regards,
--------------------
Luca Morandini
www.lucamorandini.it
--------------------
Luca Morandini ha scritto:
Folks,
I've created a bunch of spatial indexes on my DB2, but still the showing of maps is rather slow: should I re-register the spatial columns, re-deploy GeoServer or do something else to make them work ?
I have no idea, never managed to find the time and try out db2 spatial
support. David Adler is the boss here. Hope he may know more.
Cheers
Andrea
I missed the original post - too much traffic on the GeoTools/GeoServer/uDig groups.
A few questions:
1. Is the drawing of the data from other sources faster - why do you think it is an index issue?
2. What are the spatial index definitions?
3. Did you do a runstats after creating the index?
db2 runstats on table <schemaName>.<tableName> and indexes all
4. How many rows are in the table?
5. How many rows are being fetched and displayed?
Andrea Aime wrote:
Luca Morandini ha scritto:
Folks,
I've created a bunch of spatial indexes on my DB2, but still the showing of maps is rather slow: should I re-register the spatial columns, re-deploy GeoServer or do something else to make them work ?
I have no idea, never managed to find the time and try out db2 spatial
support. David Adler is the boss here. Hope he may know more.Cheers
Andrea
On 12/13/06, David Adler <dadler@anonymised.com> wrote:
I missed the original post - too much traffic on the
GeoTools/GeoServer/uDig groups.A few questions:
1. Is the drawing of the data from other sources faster - why do you
think it is an index issue?
Well, it's dog slow when it comes to drawng roads (about 29.000 rows),
and I inferred it was for the lack of indexes.
2. What are the spatial index definitions?
Usual grid sizes gathered from the spatial index advisor:
CREATE INDEX geostrade_si
ON geostrade(Shape)
EXTEND USING db2gse.SPATIAL_INDEX(17000,51000,0)
and so on...
3. Did you do a runstats after creating the index?
db2 runstats on table <schemaName>.<tableName> and indexes all
Acutally not.. I supposed DB2 was lke Oracle in this... anyway, I've
done RUNSTATS to no noticeable effect.
4. How many rows are in the table?
The biggest one is roads, about 29.000 rows.
5. How many rows are being fetched and displayed?
A few hundred I suppose... how can I gather this piece of informtion ?
Best regards,
--------------------
Luca Morandini
www.lucamorandini.it
--------------------
Hey guys,
I have no idea about the DB2 gt2 query setup, but I did find similar symptoms resulting from the ArcSDE query setup a while ago.
The issues showed up when there was a query which selected a small number of features from a very large featurecollection. My example was a small view of a roads dataset.
Two fixes caused major speedups in my map renderings:
http://jira.codehaus.org/browse/GEOT-1007
and
http://jira.codehaus.org/browse/GEOT-1006
If the exact problems that these patches fix *do* exist in the DB2 code, (and you're using a PropertyIsLike filter, luca!) then there might be some speedups. Of course these could also be totally unhelpful too!
Just thought I'd throw in a few code-points to look at.
--saul
Luca Morandini wrote:
On 12/13/06, David Adler <dadler@anonymised.com> wrote:
I missed the original post - too much traffic on the
GeoTools/GeoServer/uDig groups.