Root sampling events with a dense integer id — build_sample

One row per sample with no parent, numbered by dense_rank() over sample_key so the id is deterministic across runs; carries the root's position, time, cruise, gear, seafloor depth and — last — hex7, the root's own H3 cell exactly as sample holds it. Every browser object joins on root_id; root_sample_key is what it stands for.

Usage

build_sample_root(con, tbl = "sample_root")

Arguments

con: DuckDB connection holding sample.
tbl: name of the table to (re)create.

Value

Invisibly, the row count.

Details

hex7 is carried, never recomputed here, so sample.hex7 and sample_root.hex7 cannot disagree for a root: stamp sample with add_sample_hex7() first. On a sample without the column hex7 is NULL (like seafloor_depth_m) and a message says so; check_sample_hex7() fails such a release.