- since we are mutating the statement in a loop, start with

the same cached starting statement each time.  no issue has been observed
with the former but it could perhaps have issues w/ versioning
or eager_defaults

(cherry picked from commit d0fc7269888247517ffa16d9472f961ebec892a7)

diff --git a/lib/sqlalchemy/orm/persistence.py b/lib/sqlalchemy/orm/persistence.py
index c234225dc6c2291201652c030f237f848e56db08..fc48dec25ae631243a3a2da228ba991f24d0e5de 100644 (file)
--- a/lib/sqlalchemy/orm/persistence.py
+++ b/lib/sqlalchemy/orm/persistence.py
@@ -626,7 +626,7 @@ def _emit_update_statements(base_mapper, uowtransaction,
         stmt = table.update(clause)
         return stmt
 
-    statement = base_mapper._memo(('update', table), update_stmt)
+    cached_stmt = base_mapper._memo(('update', table), update_stmt)
 
     for (connection, paramkeys, hasvalue, has_all_defaults), \
         records in groupby(
@@ -641,6 +641,8 @@ def _emit_update_statements(base_mapper, uowtransaction,
         rows = 0
         records = list(records)
 
+        statement = cached_stmt
+
         # TODO: would be super-nice to not have to determine this boolean
         # inside the loop here, in the 99.9999% of the time there's only
         # one connection in use
@@ -649,7 +651,8 @@ def _emit_update_statements(base_mapper, uowtransaction,
             connection.dialect.supports_sane_multi_rowcount
         allow_multirow = has_all_defaults and not needs_version_id
 
-        if bookkeeping and mapper.base_mapper.eager_defaults:
+        if bookkeeping and not has_all_defaults and \
+                mapper.base_mapper.eager_defaults:
             statement = statement.return_defaults()
         elif mapper.version_id_col is not None:
             statement = statement.return_defaults(mapper.version_id_col)
@@ -736,7 +739,7 @@ def _emit_insert_statements(base_mapper, uowtransaction,
     """Emit INSERT statements corresponding to value lists collected
     by _collect_insert_commands()."""
 
-    statement = base_mapper._memo(('insert', table), table.insert)
+    cached_stmt = base_mapper._memo(('insert', table), table.insert)
 
     for (connection, pkeys, hasvalue, has_all_pks, has_all_defaults), \
         records in groupby(
@@ -748,6 +751,8 @@ def _emit_insert_statements(base_mapper, uowtransaction,
                 rec[6],
                 rec[7])):
 
+        statement = cached_stmt
+
         if not bookkeeping or \
                 (
                     has_all_defaults