Add support for CACHE and ORDER to sequences

Added new keywords :paramref:`.Sequence.cache` and
:paramref:`.Sequence.order` to :class:`.Sequence`, to allow rendering
of the CACHE parameter understood by Oracle and PostgreSQL, and the
ORDER parameter understood by Oracle.  Pull request
courtesy David Moore.

Change-Id: I082c3f8ef56ef89dbaad5da9d5695be5313b0614
Pull-request: https://bitbucket.org/zzzeek/sqlalchemy/pull-requests/96
(cherry picked from commit faa6609dac2ce6e55e0f690df3ba88c13133ec5c)

3 files changed, 22 insertions, 3 deletions

diff --git a/lib/sqlalchemy/engine/interfaces.py b/lib/sqlalchemy/engine/interfaces.py
index d0eff1cb1..afa3c0fe2 100644
--- a/lib/sqlalchemy/engine/interfaces.py
+++ b/lib/sqlalchemy/engine/interfaces.py
@@ -254,7 +254,7 @@ class Dialect(object):
           a dictionary of the form
               {'name' : str, 'start' :int, 'increment': int, 'minvalue': int,
                'maxvalue': int, 'nominvalue': bool, 'nomaxvalue': bool,
-               'cycle': bool}
+               'cycle': bool, 'cache': int, 'order': bool}
 
         Additional column attributes may be present.
         """
diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py
index bfa22c206..6768c062e 100644
--- a/lib/sqlalchemy/sql/compiler.py
+++ b/lib/sqlalchemy/sql/compiler.py
@@ -2483,6 +2483,10 @@ class DDLCompiler(Compiled):
             text += " NO MINVALUE"
         if create.element.nomaxvalue is not None:
             text += " NO MAXVALUE"
+        if create.element.cache is not None:
+            text += " CACHE %d" % create.element.cache
+        if create.element.order is True:
+            text += " ORDER"
         if create.element.cycle is not None:
             text += " CYCLE"
         return text
diff --git a/lib/sqlalchemy/sql/schema.py b/lib/sqlalchemy/sql/schema.py
index 078487bec..592dc390d 100644
--- a/lib/sqlalchemy/sql/schema.py
+++ b/lib/sqlalchemy/sql/schema.py
@@ -2120,8 +2120,8 @@ class Sequence(DefaultGenerator):
 
     def __init__(self, name, start=None, increment=None, minvalue=None,
                  maxvalue=None, nominvalue=None, nomaxvalue=None, cycle=None,
-                 schema=None, optional=False, quote=None, metadata=None,
-                 quote_schema=None,
+                 schema=None, cache=None, order=None, optional=False,
+                 quote=None, metadata=None, quote_schema=None,
                  for_update=False):
         """Construct a :class:`.Sequence` object.
 
@@ -2188,6 +2188,19 @@ class Sequence(DefaultGenerator):
          schema name when a :class:`.MetaData` is also present are the same
          as that of :paramref:`.Table.schema`.
 
+        :param cache: optional integer value; number of future values in the
+         sequence which are calculated in advance.  Renders the CACHE keyword
+         understood by Oracle and PostgreSQL.
+
+         .. versionadded:: 1.1.12
+
+        :param order: optional boolean value; if true, renders the
+         ORDER keyword, understood by Oracle, indicating the sequence is
+         definitively ordered.   May be necessary to provide deterministic
+         ordering using Oracle RAC.
+
+         .. versionadded:: 1.1.12
+
         :param optional: boolean value, when ``True``, indicates that this
          :class:`.Sequence` object only needs to be explicitly generated
          on backends that don't provide another way to generate primary
@@ -2243,6 +2256,8 @@ class Sequence(DefaultGenerator):
         self.nominvalue = nominvalue
         self.nomaxvalue = nomaxvalue
         self.cycle = cycle
+        self.cache = cache
+        self.order = order
         self.optional = optional
         if schema is BLANK_SCHEMA:
             self.schema = schema = None