toast query snippet

toast.md

We can use a varient of the pg_class disk usage queries to find how much space is used by the toast tables for each of the rendering tables.

SELECT mains.relname, 
    toasts.relpages::bigint*8192 AS "toast size", toasts.reltuples AS "toast tuples", indexes.relpages::bigint*8192 AS "toast index size"
  FROM pg_class toasts
    JOIN pg_class mains ON (toasts.oid = mains.reltoastrelid)
    LEFT JOIN pg_class indexes ON (indexes.oid = toasts.reltoastidxid)
  WHERE 
    mains.relname IN ('planet_osm_point', 'planet_osm_line', 'planet_osm_polygon');