FDO Function SpatialExtents
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Haris Kurtagic
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Some javascript/style in this post has been disabled (why?)
Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in understanding
how clients, MAP 3D , is using it. I am not sure if I understand how is it supposed
to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
Orest Halustchak
|
Some javascript/style in this post has been disabled (why?)
Hi Haris, Map3D asks for the spatial
extents first before fetching any of the geometry. The spatial extents will
define the extents of the window. The spatial extents function needs to be very
quick in this case. For Oracle, you could get it from the r-tree. Thanks, Orest. From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Robert Fortin
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In reply to this post
by Haris Kurtagic
Some javascript/style in this post has been disabled (why?)
Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents function
is the slower Map rendering will be. SDO_AGGR_MBR is probably not
efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That is
rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Haris Kurtagic
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In reply to this post
by Orest Halustchak
Some javascript/style in this post has been disabled (why?)
Can you help me little more, how
to get it from R-TREE ? I know of SDO_TUNE.Extent_OF which
is faster for some types of data. BTW, so far I tested , Map calls
it twice, once together with Count, second time only SpatialExtents. Thanks, Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Hi Haris, Map3D asks for the spatial extents
first before fetching any of the geometry. The spatial extents will define the
extents of the window. The spatial extents function needs to be very quick in
this case. For Oracle, you could get it from the r-tree. Thanks, Orest. From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Orest Halustchak
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In reply to this post
by Haris Kurtagic
Some javascript/style in this post has been disabled (why?)
Oracle saves the root mbr in one of the metadata tables. I don't have access at the moment to check. From: [hidden email] To: FDO Internals Mail List Sent: Mon Nov 17 14:54:09 2008 Subject: RE: [fdo-internals] RE: FDO Function SpatialExtents Can you help me little more, how
to get it from R-TREE ? I know of SDO_TUNE.Extent_OF which
is faster for some types of data. BTW, so far I tested , Map calls
it twice, once together with Count, second time only SpatialExtents. Thanks, Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Hi Haris, Map3D asks for the spatial extents
first before fetching any of the geometry. The spatial extents will define the
extents of the window. The spatial extents function needs to be very quick in
this case. For Oracle, you could get it from the r-tree. Thanks, Orest. From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Haris Kurtagic
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In reply to this post
by Robert Fortin
Some javascript/style in this post has been disabled (why?)
Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Traian Stanev
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Some javascript/style in this post has been disabled (why?)
Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command SelectAggregates
with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Haris Kurtagic
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In reply to this post
by Orest Halustchak
Some javascript/style in this post has been disabled (why?)
Yes, I use that info in describe
schema to get extents of spatial context. But I believe that metadata is
not MBR of geometries. I wrote as reply to Robert that now
I don’t know what SpatialExtents is supposed to return. I assume in Autodesk provider
there is special case of SpatialExtents for all geomtries in class. Shouldn’t we have two function
than. SpatialExtents is supposed to
return exact MBR of geometries in query ? Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Oracle
saves the root mbr in one of the metadata tables. I don't have access at the
moment to check. From:
[hidden email] Can you help me little more, how
to get it from R-TREE ? I know of SDO_TUNE.Extent_OF
which is faster for some types of data. BTW, so far I tested , Map calls
it twice, once together with Count, second time only SpatialExtents. Thanks, Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Hi Haris, Map3D asks for the spatial
extents first before fetching any of the geometry. The spatial extents will
define the extents of the window. The spatial extents function needs to be very
quick in this case. For Oracle, you could get it from the r-tree. Thanks, Orest. From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Haris Kurtagic
|
In reply to this post
by Traian Stanev
Some javascript/style in this post has been disabled (why?)
Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Jason Birch
|
In reply to this post
by Orest Halustchak
Some javascript/style in this post has been disabled (why?)
SDO_DIMINFO in the SDO_GEOM_METADATA_TABLE
(which has a bunch of user, etc aliases) stores the extents of each layer.
However, this isn’t guaranteed to be the data extents in real-world
situations. SDO_INDEX_METADATA_TABLE appears
to store information about the MBR, but I’m not sure how to decode it. None of
the entries in my database contain usable values in SDO_*_EXTENTS fields or in
the SDO_ROOT_MBR field (that I can tell). Do you have to read the value of the
SDO_NL_INDEX_TABLE, and then pull the value from that? Jason From: [hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Oracle saves the root mbr in one of the metadata tables. I don't
have access at the moment to check. From: [hidden email] Can you help me
little more, how to get it from R-TREE ? I know of
SDO_TUNE.Extent_OF which is faster for some types of data. BTW, so far I tested
, Map calls it twice, once together with Count, second time only
SpatialExtents. Thanks, Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Hi Haris, Map3D asks for the
spatial extents first before fetching any of the geometry. The spatial extents
will define the extents of the window. The spatial extents function needs to be
very quick in this case. For Oracle, you could get it from the r-tree. Thanks, Orest. From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for
SelectAggregates in King.Oracle. I am testing SpatialExtent function and I
need help in understanding how clients, MAP 3D , is using it. I am not sure if
I understand how is it supposed to be used. I have implemented function using Oracle
SDO_AGGR_MBR. That is rather slow process . What I noticed is that MAP 3D 2009 is
calling FDO command SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in
MAP 3D. I know I am asking about non-open source
client like MAP 3D but from what I see makes me wonder if I understand
SpatialExtents function correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Traian Stanev
|
In reply to this post
by Haris Kurtagic
Some javascript/style in this post has been disabled (why?)
Theoretically it has to return
the MBR of its argument. In practice, it doesn’t
need to be exact, since the code that uses it does not need it to be exact. You don’t have a choice
anyway, if you want it to perform at all… Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hm, but what is SpatialExtent function,
exact MBR or not ? Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Haris Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in understanding
how clients, MAP 3D , is using it. I am not sure if I understand how is it
supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command SelectAggregates
with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Dan Stoica
|
In reply to this post
by Orest Halustchak
Some javascript/style in this post has been disabled (why?)
The column in question is USER_SDO_INDEX_METADATA.SDO_ROOT_MBR Note for geodetic this value is
not accurate and brute force calculation should be used. Dan. From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Oracle
saves the root mbr in one of the metadata tables. I don't have access at the
moment to check. From:
[hidden email] Can you help me little more, how
to get it from R-TREE ? I know of SDO_TUNE.Extent_OF
which is faster for some types of data. BTW, so far I tested , Map calls
it twice, once together with Count, second time only SpatialExtents. Thanks, Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Orest
Halustchak Hi Haris, Map3D asks for the spatial
extents first before fetching any of the geometry. The spatial extents will
define the extents of the window. The spatial extents function needs to be very
quick in this case. For Oracle, you could get it from the r-tree. Thanks, Orest. From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Jason Birch
|
In reply to this post
by Jason Birch
Some javascript/style in this post has been disabled (why?)
Doh, I spoke too soon. USER_SDO_INDEX_METADATA..SDO_ROOT_MBR
does actually contain values on my setup, it’s just that my window was cutting
it off after the dimensionality info. Jason From: [hidden email]
[mailto:[hidden email]] On Behalf Of Jason Birch SDO_DIMINFO in the
SDO_GEOM_METADATA_TABLE (which has a bunch of user, etc aliases) stores the
extents of each layer. However, this isn’t guaranteed to be the
data extents in real-world situations. SDO_INDEX_METADATA_TABLE appears
to store information about the MBR, but I’m not sure how to decode it.
None of the entries in my database contain usable values in SDO_*_EXTENTS
fields or in the SDO_ROOT_MBR field (that I can tell). Do you have to
read the value of the SDO_NL_INDEX_TABLE, and then pull the value from that? _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Haris Kurtagic
|
In reply to this post
by Traian Stanev
Some javascript/style in this post has been disabled (why?)
Traian, Now I don’t understand you :) I would believe SpatialExtents
should return exact MBR value of geometries in Select query. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Theoretically it has to return
the MBR of its argument. In practice, it doesn’t need to
be exact, since the code that uses it does not need it to be exact. You don’t have a choice anyway,
if you want it to perform at all… Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can zoom
to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is SpatialExtents
supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in understanding
how clients, MAP 3D , is using it. I am not sure if I understand how is it
supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
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Traian Stanev
|
Some javascript/style in this post has been disabled (why?)
It’s a question of practicality,
not belief. J SpatialExtents exists only so
that providers which can provide a faster implementation than the naïve iteration
over all features can make that feature accessible. If you want to provide the naïve
implementation of iterating over all features and computing the union of their
MBRs, then save yourself the effort, since Map already has this fallback. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Traian, Now I don’t understand you :) I would believe SpatialExtents
should return exact MBR value of geometries in Select query. Haris From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Traian Stanev Theoretically it has to return
the MBR of its argument. In practice, it doesn’t need to
be exact, since the code that uses it does not need it to be exact. You don’t have a choice anyway,
if you want it to perform at all… Traian From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Haris Kurtagic Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR ( perhaps
that is what Orest was saying ? ) but that is not correct MBR of geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents function
(if is exists) in order to compute the extent of the data set before it starts
populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
||||||||||||||||
|
Haris Kurtagic
|
Some javascript/style in this post has been disabled (why?)
I think it is very important question. Autodesk Oracle provider is not
returning correct result if (and I think it is) SpatialExtent is supposed to
return exact MBR of geometries. I am looking now at SqlSrever
provider and there are 2 special cases for Count and SpatialEXtents for whole
layer. For those 2 special cases there
is special code and special OptimizedAggregateReader etc... What looks wrong to me is that
we used exact SpatialExtent function to return something what doesn’t need to
be exact. Shouldn’t be better to have
special command or special function to return count, extents of layer etc.. Now it looks to me that code of
provider is more complicated and also we have function which could or could not
return expected result. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev It’s a question of practicality,
not belief. J SpatialExtents exists only so
that providers which can provide a faster implementation than the naïve
iteration over all features can make that feature accessible. If you want to
provide the naïve implementation of iterating over all features and computing
the union of their MBRs, then save yourself the effort, since Map already has
this fallback. Traian From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Traian, Now I don’t understand you :) I would believe SpatialExtents
should return exact MBR value of geometries in Select query. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Theoretically it has to return
the MBR of its argument. In practice, it doesn’t need to
be exact, since the code that uses it does not need it to be exact. You don’t have a choice anyway,
if you want it to perform at all… Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding box
of all the geometries. Map does not need exact BBOX, just an extent it can zoom
to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Robert Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
||||||||||||||||
|
Haris Kurtagic
|
Some javascript/style in this post has been disabled (why?)
I have implemented in
King.Oracle special case of SpatialExtents for all geometries in class. It will not return exact extents
of geometries but will return what is written in index meatada (SDO_ROOT_MBR
from sdo_index_metadata). If there is filter set with
SelectAggregate command then correct extent will be returned ( using SDO_AGR_MBR
Oracle function ). I have implemented in such way because
MAP 3D is using SpatialExtents every time when layer is to be displayed and because
of that rendering in MAP becomes slow. I think it is not correct that
SpatialExtent will not return exact MBR but because MAP 3D is obviously very
important FDO client priorities are reordered :) I would suggest ( RFC ? ) that we
would have dedicated commands/functions which are used in typical applications. -
command to return
just “zoom extent” of layer -
command to get geometries
and keys from window query (envelope intersect) -
command to get
selection based on rectangular window -
few more... Right now providers are parsing select
command and try to discover those special cases which are basically not special
cases but standard cases coming from practical use. Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic I think it is very important
question. Autodesk Oracle provider is not
returning correct result if (and I think it is) SpatialExtent is supposed to
return exact MBR of geometries. I am looking now at SqlSrever
provider and there are 2 special cases for Count and SpatialEXtents for whole
layer. For those 2 special cases there
is special code and special OptimizedAggregateReader etc... What looks wrong to me is that
we used exact SpatialExtent function to return something what doesn’t
need to be exact. Shouldn’t be better to
have special command or special function to return count, extents of layer
etc.. Now it looks to me that code of
provider is more complicated and also we have function which could or could not
return expected result. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev It’s a question of
practicality, not belief. J SpatialExtents exists only so
that providers which can provide a faster implementation than the naïve
iteration over all features can make that feature accessible. If you want to
provide the naïve implementation of iterating over all features and computing
the union of their MBRs, then save yourself the effort, since Map already has
this fallback. Traian From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Haris Kurtagic Traian, Now I don’t understand you
:) I would believe SpatialExtents
should return exact MBR value of geometries in Select query. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Theoretically it has to return
the MBR of its argument. In practice, it doesn’t
need to be exact, since the code that uses it does not need it to be exact. You don’t have a choice
anyway, if you want it to perform at all… Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is SpatialExtents
supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
||||||||||||||||
|
Dan Stoica
|
Some javascript/style in this post has been disabled (why?)
Ø It will not return exact extents of geometries but will
return what is written in index meatada (SDO_ROOT_MBR from sdo_index_metadata). Harris, as I said before, watch
out for geodetic coordinate systems. Dan. From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic I have implemented in King.Oracle
special case of SpatialExtents for all geometries in class. It will not return exact extents
of geometries but will return what is written in index meatada (SDO_ROOT_MBR
from sdo_index_metadata). If there is filter set with
SelectAggregate command then correct extent will be returned ( using
SDO_AGR_MBR Oracle function ). I have implemented in such way
because MAP 3D is using SpatialExtents every time when layer is to be displayed
and because of that rendering in MAP becomes slow. I think it is not correct that
SpatialExtent will not return exact MBR but because MAP 3D is obviously very
important FDO client priorities are reordered :) I would suggest ( RFC ? ) that
we would have dedicated commands/functions which are used in typical applications. -
command to return
just “zoom extent” of layer -
command to get
geometries and keys from window query (envelope intersect) -
command to get
selection based on rectangular window -
few more... Right now providers are parsing
select command and try to discover those special cases which are basically not
special cases but standard cases coming from practical use. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris Kurtagic I think it is very important
question. Autodesk Oracle provider is not
returning correct result if (and I think it is) SpatialExtent is supposed to
return exact MBR of geometries. I am looking now at SqlSrever
provider and there are 2 special cases for Count and SpatialEXtents for whole
layer. For those 2 special cases there
is special code and special OptimizedAggregateReader etc... What looks wrong to me is that
we used exact SpatialExtent function to return something what doesn’t need to
be exact. Shouldn’t be better to have
special command or special function to return count, extents of layer etc.. Now it looks to me that code of
provider is more complicated and also we have function which could or could not
return expected result. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev It’s a question of practicality,
not belief. J SpatialExtents exists only so that
providers which can provide a faster implementation than the naïve iteration
over all features can make that feature accessible. If you want to provide the
naïve implementation of iterating over all features and computing the union of
their MBRs, then save yourself the effort, since Map already has this fallback. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Traian, Now I don’t understand you :) I would believe SpatialExtents
should return exact MBR value of geometries in Select query. Haris From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Traian Stanev Theoretically it has to return
the MBR of its argument. In practice, it doesn’t need to
be exact, since the code that uses it does not need it to be exact. You don’t have a choice anyway,
if you want it to perform at all… Traian From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Haris Kurtagic Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Haris Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
||||||||||||||||
|
Haris Kurtagic
|
Some javascript/style in this post has been disabled (why?)
Not sure what you mean.
SDO_ROOT_MBR is not MBR of geometries. SpatialExtent will not return
exact MBR of all geometries for class because priority is speed in MAP 3D. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Dan Stoica Ø It will not return exact extents of geometries but will
return what is written in index meatada (SDO_ROOT_MBR from sdo_index_metadata). Harris, as I said before, watch
out for geodetic coordinate systems. Dan. From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic I have implemented in
King.Oracle special case of SpatialExtents for all geometries in class. It will not return exact extents
of geometries but will return what is written in index meatada (SDO_ROOT_MBR
from sdo_index_metadata). If there is filter set with
SelectAggregate command then correct extent will be returned ( using
SDO_AGR_MBR Oracle function ). I have implemented in such way
because MAP 3D is using SpatialExtents every time when layer is to be displayed
and because of that rendering in MAP becomes slow. I think it is not correct that SpatialExtent
will not return exact MBR but because MAP 3D is obviously very important FDO
client priorities are reordered :) I would suggest ( RFC ? ) that
we would have dedicated commands/functions which are used in typical
applications. -
command to return
just “zoom extent” of layer -
command to get
geometries and keys from window query (envelope intersect) -
command to get
selection based on rectangular window -
few more... Right now providers are parsing
select command and try to discover those special cases which are basically not
special cases but standard cases coming from practical use. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic I think it is very important
question. Autodesk Oracle provider is not
returning correct result if (and I think it is) SpatialExtent is supposed to
return exact MBR of geometries. I am looking now at SqlSrever
provider and there are 2 special cases for Count and SpatialEXtents for whole
layer. For those 2 special cases there
is special code and special OptimizedAggregateReader etc... What looks wrong to me is that we
used exact SpatialExtent function to return something what doesn’t need to be
exact. Shouldn’t be better to have
special command or special function to return count, extents of layer etc.. Now it looks to me that code of provider
is more complicated and also we have function which could or could not return
expected result. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev It’s a question of practicality,
not belief. J SpatialExtents exists only so
that providers which can provide a faster implementation than the naïve iteration
over all features can make that feature accessible. If you want to provide the
naïve implementation of iterating over all features and computing the union of
their MBRs, then save yourself the effort, since Map already has this fallback. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Traian, Now I don’t understand you :) I would believe SpatialExtents
should return exact MBR value of geometries in Select query. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian Stanev Theoretically it has to return
the MBR of its argument. In practice, it doesn’t need to
be exact, since the code that uses it does not need it to be exact. You don’t have a choice anyway,
if you want it to perform at all… Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Traian Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From: [hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
||||||||||||||||
|
Haris Kurtagic
|
In reply to this post
by Dan Stoica
Some javascript/style in this post has been disabled (why?)
Perhaps I understand you now :) SDO_ROOT_MBR is not even close
to layer extent for geodetic CS. Any clue how Autodesk.Oracle
provider is calculating index extent from that SDO_ROOT_MBR for geodetic CS? Rhank you, Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Dan Stoica Ø It will not return exact extents of geometries but will
return what is written in index meatada (SDO_ROOT_MBR from sdo_index_metadata). Harris, as I said before, watch
out for geodetic coordinate systems. Dan. From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic I have implemented in
King.Oracle special case of SpatialExtents for all geometries in class. It will not return exact extents
of geometries but will return what is written in index meatada (SDO_ROOT_MBR
from sdo_index_metadata). If there is filter set with
SelectAggregate command then correct extent will be returned ( using
SDO_AGR_MBR Oracle function ). I have implemented in such way
because MAP 3D is using SpatialExtents every time when layer is to be displayed
and because of that rendering in MAP becomes slow. I think it is not correct that
SpatialExtent will not return exact MBR but because MAP 3D is obviously very
important FDO client priorities are reordered :) I would suggest ( RFC ? ) that
we would have dedicated commands/functions which are used in typical
applications. -
command to return
just “zoom extent” of layer -
command to get
geometries and keys from window query (envelope intersect) -
command to get
selection based on rectangular window -
few more... Right now providers are parsing select
command and try to discover those special cases which are basically not special
cases but standard cases coming from practical use. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic I think it is very important
question. Autodesk Oracle provider is not
returning correct result if (and I think it is) SpatialExtent is supposed to
return exact MBR of geometries. I am looking now at SqlSrever
provider and there are 2 special cases for Count and SpatialEXtents for whole
layer. For those 2 special cases there
is special code and special OptimizedAggregateReader etc... What looks wrong to me is that
we used exact SpatialExtent function to return something what doesn’t need to
be exact. Shouldn’t be better to have
special command or special function to return count, extents of layer etc.. Now it looks to me that code of
provider is more complicated and also we have function which could or could not
return expected result. Haris From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev It’s a question of practicality,
not belief. J SpatialExtents exists only so
that providers which can provide a faster implementation than the naïve
iteration over all features can make that feature accessible. If you want to
provide the naïve implementation of iterating over all features and computing
the union of their MBRs, then save yourself the effort, since Map already has this
fallback. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Traian, Now I don’t understand you :) I would believe SpatialExtents
should return exact MBR value of geometries in Select query. Haris From:
[hidden email] [mailto:[hidden email]]
On Behalf Of Traian Stanev Theoretically it has to return
the MBR of its argument. In practice, it doesn’t need to
be exact, since the code that uses it does not need it to be exact. You don’t have a choice anyway,
if you want it to perform at all… Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hm, but what is SpatialExtent
function, exact MBR or not ? Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Traian
Stanev Yes, just return the bounding
box of all the geometries. Map does not need exact BBOX, just an extent it can
zoom to in order to show something once you add the layer. Traian From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Yes, SDO_AGGR_MBR could
be slow. In Oracle there is index METADATA table with SDO_ROOT_MBR (
perhaps that is what Orest was saying ? ) but that is not correct MBR of
geometries. I understood that SelectExtents
is supposed to : return exact MBR of geometries works for SQL queries, works for
subsets of data It looks to me that Map is using
SpatialExtents it to get not necessary exact extent of layer (class) not
geometries. So my question is, is
SpatialExtents supposed to return MBR of geometries ? I think for class extent we
should have another command. Haris From: [hidden email]
[mailto:[hidden email]] On Behalf Of Robert
Fortin Map will use the SelectExtents
function (if is exists) in order to compute the extent of the data set before
it starts populating the cache. The slower the SelectExtents
function is the slower Map rendering will be. SDO_AGGR_MBR
is probably not efficient enough for that purpose. RF From:
[hidden email]
[mailto:[hidden email]] On Behalf Of Haris
Kurtagic Hi, I have implemented support for SelectAggregates in
King.Oracle. I am testing SpatialExtent function and I need help in
understanding how clients, MAP 3D , is using it. I am not sure if I understand
how is it supposed to be used. I have implemented function using Oracle SDO_AGGR_MBR. That
is rather slow process . What I noticed is that MAP 3D 2009 is calling FDO command
SelectAggregates with SpatialExtents function. That makes rendering of layers very slow in MAP 3D. I know I am asking about non-open source client like MAP 3D
but from what I see makes me wonder if I understand SpatialExtents function
correctly. Thank you, Haris _______________________________________________ fdo-internals mailing list [hidden email] http://lists.osgeo.org/mailman/listinfo/fdo-internals |
||||||||||||||||
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