Use ST_SetMetaData to specify metadata for a raster or band - PolarDB

Sets a metadata item on a raster object or a specific band. Setting the value to an empty string ('') deletes the metadata item.

Syntax

raster ST_SetMetaData(raster raster_obj,
                      text key,
                      text value);

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

Parameter	Description
`raster_obj`	The raster object whose metadata item you want to set.
`band`	The sequence number of the band whose metadata item you want to set. Valid values start from 0.
`key`	The name of the metadata item.
`value`	The value of the metadata item. To delete the metadata item, set this parameter to an empty string (`''`).

Set and retrieve the NETCDF_DIM_time metadata item at the raster level:

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

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

Set and retrieve the NETCDF_DIM_time metadata item at the band level:

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

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