PG_FUNCTION_INFO_V1() [6/13]

PG_FUNCTION_INFO_V1

(

gserialized_analyze_nd

)

This function will be called when the ANALYZE command is run on a column of the "geometry" or "geography" type.

It will need to return a stats builder function reference and a "minimum" sample rows to feed it. If we want analisys to be completely skipped we can return false and leave output vals untouched.

What we know from this call is:

    o The pg_attribute row referring to the specific column.
      Could be used to get reltuples from pg_class (which
      might quite inexact though...) and use them to set an
      appropriate minimum number of sample rows to feed to
      the stats builder. The stats builder will also receive
      a more accurate "estimation" of the number or rows.

    o The pg_type row for the specific column.
      Could be used to set stat builder / sample rows
      based on domain type (when postgis will be implemented
      that way).

Being this experimental we'll stick to a static stat_builder/sample_rows value for now.