[postgis-users] How compute the stats from a raster table.

Andrea Peri aperi2007 at gmail.com
Fri Mar 16 00:17:14 PDT 2012


>ST_SummaryStats()

Hi Pierre,

I try it ,
but i'm not sure to understand the results.

The docs say it return the stats for a given raster band of a raster coverage.
I assume this was mean It return me a single row of values for the raster table.
Instead It return me many records of type SummaryStats.

It seem to return a result for every table row.
I'm not soo skilled on the raster to well understand what is a row
table in a raster table.
I guess, perhaps, it is the tile ?
If yes, this mean it is returning the stats for every tile.

And so my quest now is how to retrieve the total stat for all the raster table.
Also I cannot try the group by because the ST_SummaryStats is not an
aggregate function.

This is the query I try:

select ST_SummaryStats(rast_column) from my_schema.my_table;

Thx,

-- 
-----------------
Andrea Peri
. . . . . . . . .
qwerty àèìòù
-----------------
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20120316/b786c9db/attachment.html>


More information about the postgis-users mailing list