[postgis-devel] AddRasterConstraints failing to create extents in raster_column view

Bborie Park dustymugs at gmail.com
Tue Apr 16 19:38:54 PDT 2013

All constraints generated through AddRasterConstraints() is done on
the data in the table.  You can always load one raster file and apply
those constraints that can are common for all raster files, usually
SRID, scale, skew, blocksize, same alignment, number of bands, pixel
types, nodata_values and out-db.

What output is there when you try to apply the extent constraint?  Are
you getting the message "Unable to get the extent of the raster
column. Attempting memory efficient (slower) approach"?

See what happens when you call the underlying extent constraint
addition function:

SELECT _add_raster_constraint_extent(SCHEMA_NAME, TABLE_NAME, COLUMN_NAME);


On Tue, Apr 16, 2013 at 6:46 PM, ryagz <raghavendra at vizexperts.com> wrote:
> Hi,
> I have very large table of about 50GB, while uploading to database i am
> dividing the images into tiles and uploading them as rows in the table.
> After inserting all the data i am Creating index, AddingRasterConstraints
> and respective overview constraints.
> The problem i am facing is AddRasterConstraints function is some times not
> creating extents in the raster_column view. While loading back the data i am
> trying to use raster_columns table to get the raster information so as to
> speed up the loading process. So, it is very important for me that
> AddRasterConstraints returns appropriate values. Can you please let me know
> wat could the problem possibly be and any information on how to debug and
> fix the problem is highly appreciated.
> Other problem i would like to report is, AddRasterConstraints is taking too
> much time. For the table mentioned above which has 64x64 tile in each row
> and 2263390 rows in the table it took about 3850 sec which was about 20% of
> total upload time(19440 sec). Is AddRasterConstraints expected to take so
> long? if so is there any way to optimize it?
> Thanks in advance.
> Ryagz
> --
> View this message in context: http://postgis.17.x6.nabble.com/AddRasterConstraints-failing-to-create-extents-in-raster-column-view-tp5003029.html
> Sent from the PostGIS - Dev mailing list archive at Nabble.com.
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