Handle CONSTRAINT TRIGGER on DB Manager/PostgreSQL.

qgis · Apr 27, 2020 · 373e1cf · 373e1cf
1 parent 37aab82
commit 373e1cf
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/python/plugins/db_manager/db_plugins/postgis/connector.py b/python/plugins/db_manager/db_plugins/postgis/connector.py
@@ -652,12 +652,15 @@ def getTableConstraints(self, table):
         version_number = int(self.getInfo()[0].split(' ')[1].split('.')[0])
         con_col_name = 'consrc' if version_number < 12 else 'conbin'
 
+        # In the query below, we exclude rows where pg_constraint.contype whose values are equal to 't'
+        # because 't' describes a CONSTRAINT TRIGGER, which is not really a constraint in the traditional
+        # sense, but a special type of trigger, and an extension to the SQL standard.
         sql = u"""SELECT c.conname, c.contype, c.condeferrable, c.condeferred, array_to_string(c.conkey, ' '), c.%s,
                          t2.relname, c.confupdtype, c.confdeltype, c.confmatchtype, array_to_string(c.confkey, ' ') FROM pg_constraint c
                   LEFT JOIN pg_class t ON c.conrelid = t.oid
                         LEFT JOIN pg_class t2 ON c.confrelid = t2.oid
                         JOIN pg_namespace nsp ON t.relnamespace = nsp.oid
-                        WHERE t.relname = %s %s """ % (con_col_name, self.quoteString(tablename), schema_where)
+                        WHERE c.contype <> 't' AND t.relname = %s %s """ % (con_col_name, self.quoteString(tablename), schema_where)
 
         c = self._execute(None, sql)
         res = self._fetchall(c)