Name
ST_BandMetaData — Returns basic meta data for a specific raster band. band num 1 is assumed if none-specified.
Synopsis
(1) record ST_BandMetaData(raster rast, integer band=1);
(2) record ST_BandMetaData(raster rast, integer[] band);
Descrizione
Returns basic meta data about a raster band. Columns returned: pixeltype, nodatavalue, isoutdb, path, outdbbandnum, filesize, filetimestamp.
![[Note]](../images/note.png)
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If raster contains no bands then an error is thrown. |
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If band has no NODATA value, nodatavalue are NULL. |
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If isoutdb is False, path, outdbbandnum, filesize and filetimestamp are NULL. If outdb access is disabled, filesize and filetimestamp will also be NULL. |
Enhanced: 2.5.0 to include outdbbandnum, filesize and filetimestamp for outdb rasters.
Examples: Variant 1
SELECT
rid,
(foo.md).*
FROM (
SELECT
rid,
ST_BandMetaData(rast, 1) AS md
FROM dummy_rast
WHERE rid=2
) As foo;
rid | pixeltype | nodatavalue | isoutdb | path | outdbbandnum
-----+-----------+---- --------+---------+------+--------------
2 | 8BUI | 0 | f | |
Examples: Variant 2
WITH foo AS (
SELECT
ST_AddBand(NULL::raster, '/home/pele/devel/geo/postgis-git/raster/test/regress/loader/Projected.tif', NULL::int[]) AS rast
)
SELECT
*
FROM ST_BandMetadata(
(SELECT rast FROM foo),
ARRAY[1,3,2]::int[]
);
bandnum | pixeltype | nodatavalue | isoutdb | path | outdbbandnum | filesize | filetimestamp |
---------+-----------+-------------+---------+--------------------------------------------------------------------------------+---------------+----------+---------------+-
1 | 8BUI | | t | /home/pele/devel/geo/postgis-git/raster/test/regress/loader/Projected.tif | 1 | 12345 | 1521807257 |
3 | 8BUI | | t | /home/pele/devel/geo/postgis-git/raster/test/regress/loader/Projected.tif | 3 | 12345 | 1521807257 |
2 | 8BUI | | t | /home/pele/devel/geo/postgis-git/raster/test/regress/loader/Projected.tif | 2 | 12345 | 1521807257 |