ORM executemany returning

Build on #5401 to allow the ORM to take advanage
of executemany INSERT + RETURNING.

Implemented the feature

updated tests

to support INSERT DEFAULT VALUES, needed to come up with
a new syntax for compiler INSERT INTO table (anycol) VALUES (DEFAULT)
which can then be iterated out for executemany.

Added graceful degrade to plain executemany for PostgreSQL <= 8.2

Renamed EXECUTEMANY_DEFAULT to EXECUTEMANY_PLAIN

Fix issue where unicode identifiers or parameter names wouldn't
work with execute_values() under Py2K, because we have to
encode the statement and therefore have to encode the
insert_single_values_expr too.

Correct issue from #5401 to support executemany + return_defaults
for a PK that is explicitly pre-generated, meaning we aren't actually
getting RETURNING but need to return it from compiled_parameters.

Fixes: #5263
Change-Id: Id68e5c158c4f9ebc33b61c06a448907921c2a657

1 files changed, 8 insertions, 0 deletions

diff --git a/lib/sqlalchemy/testing/assertsql.py b/lib/sqlalchemy/testing/assertsql.py
index ef324635e..caf61a806 100644
--- a/lib/sqlalchemy/testing/assertsql.py
+++ b/lib/sqlalchemy/testing/assertsql.py
@@ -325,6 +325,14 @@ class EachOf(AssertRule):
             super(EachOf, self).no_more_statements()
 
 
+class Conditional(EachOf):
+    def __init__(self, condition, rules, else_rules):
+        if condition:
+            super(Conditional, self).__init__(*rules)
+        else:
+            super(Conditional, self).__init__(*else_rules)
+
+
 class Or(AllOf):
     def process_statement(self, execute_observed):
         for rule in self.rules: