[postgis-devel] [WKT Raster] Clarification of nodata_values column

[Mateusz Loskot]

Hi,

The spec [1] specifies the nodata_values as follows:

"An array of nodata values, one per band. The entry may be NULL to
indicate no nodata values."

What the second sentence actually means?
I think there are a couple of interpretations possible:

1) array entry is NULL: {NULL}

2) array element entry is NULL: {1.23, NULL, -9999}


My second question, is empty field allowed for nodata_values?
I think it's not and array_length(nodata_values, 1) should always
report value equal to number of bands.

Perhaps it's worth to clarify the spec.

[1] http://trac.osgeo.org/postgis/wiki/WKTRaster/SpecificationFinal01

Best regards,
-- 
Mateusz Loskot, http://mateusz.loskot.net