aisdb.database.sql_query_strings module
- aisdb.database.sql_query_strings.has_mmsi(*, alias, mmsi, **_)[source]
SQL callback selecting a single vessel identifier
- Parameters:
alias (string) – the ‘alias’ in a ‘WITH tablename AS alias …’ SQL statement
mmsi (int) – vessel identifier
- Returns:
SQL code (string)
- aisdb.database.sql_query_strings.in_bbox(*, alias, xmin, xmax, ymin, ymax, **_)[source]
SQL callback restricting vessels in bounding box region
- Parameters:
alias (string) – the ‘alias’ in a ‘WITH tablename AS alias …’ SQL statement
xmin (float) – minimum longitude
xmax (float) – maximum longitude
ymin (float) – minimum latitude
ymax (float) – maximum latitude
- Returns:
SQL code (string)
- aisdb.database.sql_query_strings.in_bbox_geom(*, alias, xmin, xmax, ymin, ymax, **_)[source]
PostGIS-optimized SQL callback using GIST spatial index for bounding box queries. This is the PREFERRED method when geom column exists with GIST index.
- Parameters:
alias (string) – table alias in SQL query
xmin (float) – minimum longitude
xmax (float) – maximum longitude
ymin (float) – minimum latitude
ymax (float) – maximum latitude
- Returns:
SQL code (string) using PostGIS spatial operators
- aisdb.database.sql_query_strings.in_mmsi(*, alias, mmsis, **_)[source]
SQL callback selecting multiple vessel identifiers
- Parameters:
alias (string) – the ‘alias’ in a ‘WITH tablename AS alias …’ SQL statement
mmsis (tuple) – tuple of vessel identifiers (int)
- Returns:
SQL code (string)
- aisdb.database.sql_query_strings.in_polygon_geom(*, alias, polygon_wkt, srid=4326, **_)[source]
polygon_wkt: ‘POLYGON((lon lat, …))’ in WKT, srid default 4326. Uses && for fast reject + ST_Intersects for correctness.