Specify or delete metadata for a raster or band with ST_SetMetaData - PolarDB

Sets a metadata item for a raster object or a specific band.

Syntax

raster ST_SetMetaData(raster raster_obj,
                      text key,
                      text value);
raster ST_MetaData(raster raster_obj,
                   integer band,
                   text key,
                   text value);

Parameters

Parameter	Description
`raster_obj`	The raster object on which to set the metadata item.
`band`	The sequence number of the band on which to set the metadata item. Valid values start from 0.
`key`	The name of the metadata item.
`value`	The value of the metadata item.

Usage notes

To delete a metadata item, pass an empty string ('') as the value.

Examples

Set and retrieve a metadata item on a raster object:

SELECT ST_MetaData(ST_SetMetaData(rast, 'NETCDF_DIM_time', '12345'), 'NETCDF_DIM_time')
FROM raster_table

st_metadata
------------
12345

Set and retrieve a metadata item on a specific band:

SELECT ST_MetaData(ST_SetMetaData(rast, 0, 'NETCDF_DIM_time', '12345'), 0, 'NETCDF_DIM_time')
FROM raster_table

st_metadata
------------
12345