fgeometrycolumn
fgeometrycolumn is a reference to the field that stores the name of a geometry column within the PostGIS geometry metadata. In practice, this is usually written as f_geometry_column in PostGIS documentation and database catalogs. The term may appear without the underscore in older sources or code, but the concept remains the same: it identifies which column in a table contains geometric data.
In PostgreSQL databases with PostGIS enabled, geometry columns are tracked in a system catalog called geometry_columns.
Usage and purpose: The f_geometry_column field enables tools and functions to discover and work with spatial
Example: SELECT f_table_schema, f_table_name, f_geometry_column, type, srid FROM geometry_columns WHERE f_table_name = 'roads';
Notes: The geometry_columns metadata remains a standard reference in PostGIS, though newer workflows may rely more