select_sql must yield sample_key, sample_type, parent_sample_key,
root_sample_key, dataset_key, grid_key, cruise_key, latitude,
longitude, datetime, depth_min_m, depth_max_m, tow_type by name;
geom is minted here as ST_Point(longitude, latitude). tow_type is the net
gear code (ichthyo tow/net grains: C1/CB/CV/PV oblique/vertical, MT manta), NULL
for gears/datasets without one. Prefer build_sample_reference() for the central
Phase-2 build; use this for per-dataset (Phase 3) appends.
Arguments
- con
a DuckDB connection (open via
get_duckdb_con())- select_sql
a SELECT producing the canonical
obscolumns by name- sample_tbl
target table (default
"sample")