This function compresses a pcpatch object based on the specified compression method.


pcpatch ST_compress(pcpatch pc, text global_compression_schema default '', text compression_config default '');


Parameter Description
pc The pcpatch object.
global_compression_schema The compression schema.
compression_config The compression configuration item that specifies the compression algorithm for specific dimensions.


Valid values of the global_compression_schema parameter include:

auto           -- determined by pcid
laz             -- no compression config supported
ght            -- is discarded

If the global_compression_schema parameter is set to dimension, valid values of the compression_config parameter include:

auto -- determined automatically, from values stats
zlib -- deflate compression
sigbits -- significant bits removal
rle -- run-length encoding


SELECT ST_asText(ST_Compress(ST_MakePatch(1, ARRAY[-126.99,45.01,1,0, -126.98,45.02,2,0, -126.97,45.03,3,0])));