Take into account supersession information to filter out irrelevant transformations

1 files changed, 28 insertions, 0 deletions

diff --git a/scripts/build_db.py b/scripts/build_db.py
index 77f53fd9..46bef8c8 100755
--- a/scripts/build_db.py
+++ b/scripts/build_db.py
@@ -518,6 +518,33 @@ def fill_alias(proj_db_cursor):
             else:
                 print('Cannot find datum %s in geodetic_datum or vertical_datum' % (code))
 
+
+def find_table(proj_db_cursor, code):
+    for table_name in ('helmert_transformation', 'grid_transformation', 'concatenated_operation'):
+        proj_db_cursor.execute('SELECT name FROM %s WHERE code = ?' % table_name, (code,))
+        row = proj_db_cursor.fetchone()
+        if row is not None:
+            return row[0], table_name
+    return None
+
+def fill_supersession(proj_db_cursor):
+    proj_db_cursor.execute("SELECT object_code, superseded_by FROM epsg.epsg_supersession WHERE object_table_name = 'epsg_coordoperation' AND object_code != superseded_by")
+    for row in proj_db_cursor.fetchall():
+        code, superseded_by = row
+        proj_db_cursor.execute('SELECT 1 FROM coordinate_operation_view WHERE code = ?', (code,))
+        if proj_db_cursor.fetchone() is None:
+            print('Skipping supersession of %d since it has not been imported' % code)
+            continue
+
+        src_name, superseded_table_name = find_table(proj_db_cursor, code)
+        dst_name, replacement_table_name = find_table(proj_db_cursor, superseded_by)
+        assert superseded_table_name, row
+        assert replacement_table_name, row
+        if superseded_table_name == 'grid_transformation' and replacement_table_name == 'grid_transformation' and src_name.startswith('NAD27 to NAD83'):
+            print('Skipping supersession of %d (%s) by %d (%s)' % (code, src_name, superseded_by, dst_name))
+            continue
+        proj_db_cursor.execute("INSERT INTO supersession VALUES (?,'EPSG',?,?,'EPSG',?,'EPSG')", (superseded_table_name, code, replacement_table_name, superseded_by))
+
 def report_non_imported_operations(proj_db_cursor):
     proj_db_cursor.execute("SELECT coord_op_code, coord_op_type, coord_op_name, coord_op_method_code, coord_op_method_name, source_crs_code, target_crs_code, area_of_use_code, coord_op_accuracy, epsg_coordoperation.deprecated FROM epsg.epsg_coordoperation LEFT JOIN epsg.epsg_coordoperationmethod USING (coord_op_method_code) WHERE coord_op_code NOT IN (SELECT code FROM coordinate_operation_with_conversion_view)")
     rows = []
@@ -563,6 +590,7 @@ fill_grid_transformation(proj_db_cursor)
 fill_other_transformation(proj_db_cursor)
 fill_concatenated_operation(proj_db_cursor)
 fill_alias(proj_db_cursor)
+fill_supersession(proj_db_cursor)
 non_imported_operations = report_non_imported_operations(proj_db_cursor)
 
 proj_db_cursor.close()