ST_MemSize — Returns the amount of space (in bytes) the geometry takes.
integer ST_MemSize(geometry geomA
Returns the amount of space (in bytes) the geometry takes.
This is a nice compliment to PostgreSQL built in functions pg_column_size, pg_size_pretty, pg_relation_size, pg_total_relation_size.
pg_relation_size which gives the byte size of a table may return byte size lower than ST_MemSize. This is because pg_relation_size does not add toasted table contribution and large geometries are stored in TOAST tables.
pg_total_relation_size - includes, the table, the toasted tables, and the indexes.
pg_column_size returns how much space a geometry would take in a column considering compression, so may be lower than ST_MemSize
This function supports 3d and will not drop the z-index.
This method supports Circular Strings and Curves
This function supports Polyhedral surfaces.
This function supports Triangles and Triangulated Irregular Network Surfaces (TIN).
Changed: 2.2.0 name changed to ST_MemSize to follow naming convention. In prior versions this function was called ST_Mem_Size, old name deprecated though still available.
--Return how much byte space Boston takes up in our Mass data set SELECT pg_size_pretty(SUM(ST_MemSize(the_geom))) as totgeomsum, pg_size_pretty(SUM(CASE WHEN town = 'BOSTON' THEN ST_MemSize(the_geom) ELSE 0 END)) As bossum, CAST(SUM(CASE WHEN town = 'BOSTON' THEN ST_MemSize(the_geom) ELSE 0 END)*1.00 / SUM(ST_MemSize(the_geom))*100 As numeric(10,2)) As perbos FROM towns; totgeomsum bossum perbos ---------- ------ ------ 1522 kB 30 kB 1.99 SELECT ST_MemSize(ST_GeomFromText('CIRCULARSTRING(220268 150415,220227 150505,220227 150406)')); --- 73 --What percentage of our table is taken up by just the geometry SELECT pg_total_relation_size('public.neighborhoods') As fulltable_size, sum(ST_MemSize(the_geom)) As geomsize, sum(ST_MemSize(the_geom))*1.00/pg_total_relation_size('public.neighborhoods')*100 As pergeom FROM neighborhoods; fulltable_size geomsize pergeom ------------------------------------------------ 262144 96238 36.71188354492187500000