factored out uses_sequences_for_inserts() into

preexecute_sequence dialect attribute

6 files changed, 8 insertions, 13 deletions

diff --git a/lib/sqlalchemy/databases/firebird.py b/lib/sqlalchemy/databases/firebird.py
index d520046d0..b25a8de02 100644
--- a/lib/sqlalchemy/databases/firebird.py
+++ b/lib/sqlalchemy/databases/firebird.py
@@ -103,6 +103,7 @@ class FBExecutionContext(default.DefaultExecutionContext):
 class FBDialect(default.DefaultDialect):
     supports_sane_rowcount = False
     max_identifier_length = 31
+    preexecute_sequences = True
 
     def __init__(self, type_conv=200, concurrency_level=1, **kwargs):
         default.DefaultDialect.__init__(self, **kwargs)
@@ -306,9 +307,6 @@ class FBCompiler(compiler.DefaultCompiler):
         else:
             return func.name
 
-    def uses_sequences_for_inserts(self):
-        return True
-        
     def visit_sequence(self, seq):
         return "gen_id(" + seq.name + ", 1)"
         
diff --git a/lib/sqlalchemy/databases/oracle.py b/lib/sqlalchemy/databases/oracle.py
index d0122c7a4..fb5b512e2 100644
--- a/lib/sqlalchemy/databases/oracle.py
+++ b/lib/sqlalchemy/databases/oracle.py
@@ -237,6 +237,7 @@ class OracleDialect(default.DefaultDialect):
     max_identifier_length = 30
     supports_sane_rowcount = True
     supports_sane_multi_rowcount = False
+    preexecute_sequences = True
 
     def __init__(self, use_ansi=True, auto_setinputsizes=True, auto_convert_lobs=True, threaded=True, allow_twophase=True, **kwargs):
         default.DefaultDialect.__init__(self, default_paramstyle='named', **kwargs)
@@ -594,9 +595,6 @@ class OracleCompiler(compiler.DefaultCompiler):
     def visit_outer_join_column(self, vc):
         return self.process(vc.column) + "(+)"
         
-    def uses_sequences_for_inserts(self):
-        return True
-
     def visit_sequence(self, seq):
         return self.dialect.identifier_preparer.format_sequence(seq) + ".nextval"
         
diff --git a/lib/sqlalchemy/databases/postgres.py b/lib/sqlalchemy/databases/postgres.py
index a5c77f206..701114b17 100644
--- a/lib/sqlalchemy/databases/postgres.py
+++ b/lib/sqlalchemy/databases/postgres.py
@@ -228,6 +228,7 @@ class PGDialect(default.DefaultDialect):
     max_identifier_length = 63
     supports_sane_rowcount = True
     supports_sane_multi_rowcount = False
+    preexecute_sequences = True
 
     def __init__(self, use_oids=False, server_side_cursors=False, **kwargs):
         default.DefaultDialect.__init__(self, default_paramstyle='pyformat', **kwargs)
@@ -543,9 +544,6 @@ class PGCompiler(compiler.DefaultCompiler):
         }
     )
 
-    def uses_sequences_for_inserts(self):
-        return True
-
     def visit_sequence(self, seq):
         if seq.optional:
             return None
diff --git a/lib/sqlalchemy/engine/base.py b/lib/sqlalchemy/engine/base.py
index c7364721f..1ab05fe03 100644
--- a/lib/sqlalchemy/engine/base.py
+++ b/lib/sqlalchemy/engine/base.py
@@ -79,6 +79,9 @@ class Dialect(object):
       Indicate whether the dialect properly implements rowcount for ``UPDATE`` and ``DELETE`` statements
       when executed via executemany.
 
+    preexecute_sequences
+      Indicate if the dialect should pre-execute sequences on primary key columns during an INSERT,
+      if it's desired that the new row's primary key be available after execution.
     """
 
     def create_connect_args(self, url):
diff --git a/lib/sqlalchemy/engine/default.py b/lib/sqlalchemy/engine/default.py
index 09d17f923..578b19d16 100644
--- a/lib/sqlalchemy/engine/default.py
+++ b/lib/sqlalchemy/engine/default.py
@@ -31,6 +31,7 @@ class DefaultDialect(base.Dialect):
     max_identifier_length = 9999
     supports_sane_rowcount = True
     supports_sane_multi_rowcount = True
+    preexecute_sequences = False
 
     def __init__(self, convert_unicode=False, encoding='utf-8', default_paramstyle='named', paramstyle=None, dbapi=None, **kwargs):
         self.convert_unicode = convert_unicode
diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py
index 7f9d0e31b..1cfebdc27 100644
--- a/lib/sqlalchemy/sql/compiler.py
+++ b/lib/sqlalchemy/sql/compiler.py
@@ -610,9 +610,6 @@ class DefaultCompiler(engine.Compiled, visitors.ClauseVisitor):
         return (self.process(join.left, asfrom=True) + (join.isouter and " LEFT OUTER JOIN " or " JOIN ") + \
             self.process(join.right, asfrom=True) + " ON " + self.process(join.onclause))
 
-    def uses_sequences_for_inserts(self):
-        return False
-
     def visit_sequence(self, seq):
         return None
 
@@ -688,7 +685,7 @@ class DefaultCompiler(engine.Compiled, visitors.ClauseVisitor):
                 values.append((c, value))
             elif isinstance(c, schema.Column):
                 if self.isinsert:
-                    if c.primary_key and self.uses_sequences_for_inserts() and not self.inline:
+                    if c.primary_key and self.dialect.preexecute_sequences and not self.inline:
                         values.append((c, create_bind_param(c, None)))
                         self.prefetch.add(c)
                     elif isinstance(c.default, schema.ColumnDefault):