Use ST_Parent to return the parent of an H3 grid - PolarDB

Returns the parent grid of an H3-encoded geographic grid at the specified level.

Syntax

h3grid ST_Parent(h3grid code, integer level)

Parameter	Description
`code`	The H3-encoded geographic grid object.
`level`	The target level of the parent grid. If omitted, defaults to one level above the current level of `code`.

Return the immediate parent (default behavior)

Omit the level parameter to get the direct parent at the next coarser level:

SELECT ST_AsText(ST_Parent(ST_H3FromText('884a126689fffff')));

Output:

    st_astext
-----------------
 874a12668ffffff

Return an ancestor at a specific level

Pass a target level to get a coarser ancestor:

SELECT ST_AsText(ST_Parent(ST_H3FromText('884a126689fffff'), 2));

Output:

    st_astext
-----------------
 824a17fffffffff