Fix: Fix the query to check indexes and fix tests

Author: adrien-berchet

geoalchemy2/admin/dialects/postgresql.py

@@ -72,24 +72,32 @@ def reflect_geometry_column(inspector, table, column_info):
     else:
         schema_part = ""
 
-    has_index_query = """SELECT (indexrelid IS NOT NULL) AS has_index
-        FROM (
-            SELECT
-                    n.nspname,
-                    c.relname,
-                    c.oid AS relid,
-                    a.attname,
-                    a.attnum
-            FROM pg_attribute a
-            INNER JOIN pg_class c ON (a.attrelid=c.oid)
-            INNER JOIN pg_type t ON (a.atttypid=t.oid)
-            INNER JOIN pg_namespace n ON (c.relnamespace=n.oid)
-            WHERE c.relkind='r'
-        ) g
-        LEFT JOIN pg_index i ON (g.relid = i.indrelid AND g.attnum = ANY(i.indkey))
-        WHERE relname = '{}' AND attname = '{}'{};
-    """.format(
-        table.name, column_info["name"], schema_part
+    # Check if the column has a spatial index (the regular expression checks for the column name
+    # in the index definition, which is required for functional indexes)
+    has_index_query = """SELECT EXISTS (
+        SELECT 1
+        FROM pg_class t
+        JOIN pg_namespace n ON n.oid = t.relnamespace
+        JOIN pg_index ix ON t.oid = ix.indrelid
+        JOIN pg_class i ON i.oid = ix.indexrelid
+        JOIN pg_am am ON i.relam = am.oid
+        WHERE
+            t.relname = '{table_name}'{schema_part}
+            AND am.amname = 'gist'
+            AND (
+                EXISTS (
+                    SELECT 1
+                    FROM pg_attribute a
+                    WHERE a.attrelid = t.oid
+                    AND a.attnum = ANY(ix.indkey)
+                    AND a.attname = '{col_name}'
+                )
+                OR pg_get_indexdef(
+                    ix.indexrelid
+                ) ~ '(^|[^a-zA-Z0-9_])("?{col_name}"?)($|[^a-zA-Z0-9_])'
+            )
+    );""".format(
+        table_name=table.name, col_name="rast", schema_part=schema_part
     )
     spatial_index = inspector.bind.execute(text(has_index_query)).scalar()
 

tests/schema_fixtures.py

@@ -198,7 +198,7 @@ class Lake(base):
                 geom_geog_no_idx = Column(
                     Geography(geometry_type="LINESTRING", spatial_index=False)
                 )
-                rast = Column(Raster())
+                rast = Column(Raster(spatial_index=True))
                 rast_no_idx = Column(Raster(spatial_index=False))
 
     return metadata

tests/test_functional.py

@@ -1243,6 +1243,18 @@ def test_reflection(self, conn, setup_reflection_tables, dialect_name):
                 assert type_.srid == 4326
                 assert type_.dimension == 2
 
+                type_ = t.c.rast.type
+                assert isinstance(type_, Raster)
+                assert type_.geometry_type is None
+                assert type_.srid == -1
+                assert type_.dimension is None
+
+                type_ = t.c.rast_no_idx.type
+                assert isinstance(type_, Raster)
+                assert type_.geometry_type is None
+                assert type_.srid == -1
+                assert type_.dimension is None
+
         # Drop the table
         t.drop(bind=conn)