diff --git a/swh/storage/db.py b/swh/storage/db.py
index 874ccdb7..d00e9849 100644
--- a/swh/storage/db.py
+++ b/swh/storage/db.py
@@ -1,83 +1,97 @@
 # Copyright (C) 2015  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import psycopg2
 
 from contextlib import contextmanager
 
 TMP_CONTENT_TABLE = 'tmp_content'
 
 
+def stored_procedure(stored_proc):
+    """decorator to execute remote stored procedure, specified as argument
+
+    Generally, the body of the decorated function should be empty. If it is
+    not, the stored procedure will be executed first; the function body then.
+
+    """
+    def wrap(meth):
+        def _meth(self, *args, **kwargs):
+            cur = kwargs.get('cur', None)
+            self._cursor(cur).execute('SELECT %s()' % stored_proc)
+            meth(self, *args, **kwargs)
+        return _meth
+    return wrap
+
+
 class Db:
     """Proxy to the SWH DB, with wrappers around stored procedures
 
     """
 
     @classmethod
     def connect(cls, *args, **kwargs):
         """factory method to create a DB proxy
 
         Accepts all arguments of psycopg2.connect; only some specific
         possibilities are reported below.
 
         Args:
             connstring: libpq2 connection string
 
         """
         conn = psycopg2.connect(*args, **kwargs)
         return cls(conn)
 
     def _cursor(self, cur_arg):
         """get a cursor: from cur_arg if given, or a fresh one otherwise
 
         meant to avoid boilerplate if/then/else in methods that proxy stored
         procedures
 
         """
         if cur_arg is not None:
             return cur_arg
         # elif self.cur is not None:
         #     return self.cur
         else:
             return self.conn.cursor()
 
     def __init__(self, conn):
         """create a DB proxy
 
         Args:
             conn: psycopg2 connection to the SWH DB
 
         """
         self.conn = conn
 
     @contextmanager
     def transaction(self):
         """context manager to execute within a DB transaction
 
         Yields:
             a psycopg2 cursor
 
         """
         with self.conn.cursor() as cur:
             try:
                 yield cur
                 self.conn.commit()
             except:
                 if not self.conn.closed:
                     self.conn.rollback()
                 raise
 
-    # @stored_procedure('swh_content_mktemp')
-    def content_mktemp(self, cur=None):
-        self._cursor(cur).execute('SELECT swh_content_mktemp()')
+    @stored_procedure('swh_content_mktemp')
+    def content_mktemp(self, cur=None): pass
 
     def content_copy_to_temp(self, fileobj, cur=None):
         self._cursor(cur) \
             .copy_from(fileobj, TMP_CONTENT_TABLE,
                        columns=('sha1', 'sha1_git', 'sha256', 'length'))
 
-    # @stored_procedure('swh_content_add')
-    def content_add_from_temp(self, cur):
-        self._cursor(cur).execute('SELECT swh_content_add()')
+    @stored_procedure('swh_content_add')
+    def content_add_from_temp(self, cur=None): pass