also add support for onupdate as we'd like this to fire off if an UPDATE actually

happens on the table

1 files changed, 31 insertions, 13 deletions

diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py
index 4b1b9bd5d..7aee5da81 100644
--- a/lib/sqlalchemy/sql/compiler.py
+++ b/lib/sqlalchemy/sql/compiler.py
@@ -1140,23 +1140,41 @@ class SQLCompiler(engine.Compiled):
         # special logic that only occurs for multi-table UPDATE 
         # statements
         if extra_tables and stmt.parameters:
+            assert self.isupdate
+            affected_tables = set()
             for t in extra_tables:
                 for c in t.c:
                     if c in stmt.parameters:
+                        affected_tables.add(t)
                         check_columns[c.key] = c
-
-            for c in check_columns.values():
-                value = stmt.parameters[c]
-                if sql._is_literal(value):
-                    value = self._create_crud_bind_param(
-                                    c, value, required=value is required)
-                elif c.primary_key and implicit_returning:
-                    self.returning.append(c)
-                    value = self.process(value.self_group())
-                else:
-                    self.postfetch.append(c)
-                    value = self.process(value.self_group())
-                values.append((c, value))
+                        value = stmt.parameters[c]
+                        if sql._is_literal(value):
+                            value = self._create_crud_bind_param(
+                                            c, value, required=value is required)
+                        else:
+                            self.postfetch.append(c)
+                            value = self.process(value.self_group())
+                        values.append((c, value))
+            # determine tables which are actually
+            # to be updated - process onupdate and 
+            # server_onupdate for these
+            for t in affected_tables:
+                for c in t.c:
+                    if c in stmt.parameters:
+                        continue
+                    elif c.onupdate is not None and not c.onupdate.is_sequence:
+                        if c.onupdate.is_clause_element:
+                            values.append(
+                                (c, self.process(c.onupdate.arg.self_group()))
+                            )
+                            self.postfetch.append(c)
+                        else:
+                            values.append(
+                                (c, self._create_crud_bind_param(c, None))
+                            )
+                            self.prefetch.append(c)
+                    elif c.server_onupdate is not None:
+                        self.postfetch.append(c)
 
         # iterating through columns at the top to maintain ordering.
         # otherwise we might iterate through individual sets of