db.define_table(...table_hash=...) to override hash in .table file, thanks dmvieira

VERSION

@@ -1 +1 @@
-Version 2.9.5-trunk+timestamp.2014.03.29.17.06.19
+Version 2.9.5-trunk+timestamp.2014.03.29.17.18.01

gluon/dal.py

@@ -7648,6 +7648,9 @@ class DAL(object):
         folder: where .table files will be created. Automatically set within
             web2py. Use an explicit path when using DAL outside web2py
         db_codec: string encoding of the database (default: 'UTF-8')
+        table_hash: database identifier with .tables. If your connection hash 
+                    change you can still using old .tables if they have db_hash   
+                    as prefix
         check_reserved: list of adapters to check tablenames and column names
             against sql/nosql reserved keywords. Defaults to `None`
 
@@ -7798,7 +7801,7 @@ class DAL(object):
                  bigint_id=False, debug=False, lazy_tables=False,
                  db_uid=None, do_connect=True,
                  after_connection=None, tables=None, ignore_field_case=True,
-                 entity_quoting=False):
+                 entity_quoting=False, table_hash=None):
 
         if uri == '<zombie>' and db_uid is not None: return
         if not decode_credentials:
@@ -7887,7 +7890,7 @@ class DAL(object):
                                         entity_quoting=entity_quoting)
             migrate = fake_migrate = False
         adapter = self._adapter
-        self._uri_hash = hashlib_md5(adapter.uri).hexdigest()
+        self._uri_hash = table_hash or hashlib_md5(adapter.uri).hexdigest()
         self.check_reserved = check_reserved
         if self.check_reserved:
             from reserved_sql_keywords import ADAPTERS as RSK