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diff --git a/pynslcd/cache.py b/pynslcd/cache.py
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+
+# cache.py - caching layer for pynslcd
+#
+# Copyright (C) 2012 Arthur de Jong
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301 USA
+
+import datetime
+import itertools
+import os
+import sys
+
+import sqlite3
+
+
+# TODO: probably create a config table
+
+# FIXME: store the cache in the right place and make it configurable
+filename = '/var/run/nslcd/cache.sqlite'
+dirname = os.path.dirname(filename)
+if not os.path.isdir(dirname):
+    os.mkdir(dirname)
+con = sqlite3.connect(filename,
+                detect_types=sqlite3.PARSE_DECLTYPES, check_same_thread=False)
+con.row_factory = sqlite3.Row
+
+# FIXME: have some way to remove stale entries from the cache if all items from LDAP are queried (perhas use TTL from all request)
+
+# set up the database
+con.executescript('''
+
+    -- store temporary tables in memory
+    PRAGMA temp_store = MEMORY;
+
+    -- disable sync() on database (corruption on disk failure)
+    PRAGMA synchronous = OFF;
+
+    -- put journal in memory (corruption if crash during transaction)
+    PRAGMA journal_mode = MEMORY;
+
+    -- tables for alias cache
+    CREATE TABLE IF NOT EXISTS `alias_cache`
+      ( `cn` TEXT PRIMARY KEY COLLATE NOCASE,
+        `mtime` TIMESTAMP NOT NULL );
+    CREATE TABLE IF NOT EXISTS `alias_1_cache`
+      ( `alias` TEXT NOT NULL COLLATE NOCASE,
+        `rfc822MailMember` TEXT NOT NULL,
+        FOREIGN KEY(`alias`) REFERENCES `alias_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `alias_1_idx` ON `alias_1_cache`(`alias`);
+
+    -- table for ethernet cache
+    CREATE TABLE IF NOT EXISTS `ether_cache`
+      ( `cn` TEXT NOT NULL COLLATE NOCASE,
+        `macAddress` TEXT NOT NULL COLLATE NOCASE,
+        `mtime` TIMESTAMP NOT NULL,
+        UNIQUE (`cn`, `macAddress`) );
+
+    -- table for group cache
+    CREATE TABLE IF NOT EXISTS `group_cache`
+      ( `cn` TEXT PRIMARY KEY,
+        `userPassword` TEXT,
+        `gidNumber` INTEGER NOT NULL UNIQUE,
+        `mtime` TIMESTAMP NOT NULL );
+    CREATE TABLE IF NOT EXISTS `group_3_cache`
+      ( `group` TEXT NOT NULL,
+        `memberUid` TEXT NOT NULL,
+        FOREIGN KEY(`group`) REFERENCES `group_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `group_3_idx` ON `group_3_cache`(`group`);
+
+    -- tables for host cache
+    CREATE TABLE IF NOT EXISTS `host_cache`
+      ( `cn` TEXT PRIMARY KEY COLLATE NOCASE,
+        `mtime` TIMESTAMP NOT NULL );
+    CREATE TABLE IF NOT EXISTS `host_1_cache`
+      ( `host` TEXT NOT NULL COLLATE NOCASE,
+        `cn` TEXT NOT NULL COLLATE NOCASE,
+        FOREIGN KEY(`host`) REFERENCES `host_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `host_1_idx` ON `host_1_cache`(`host`);
+    CREATE TABLE IF NOT EXISTS `host_2_cache`
+      ( `host` TEXT NOT NULL COLLATE NOCASE,
+        `ipHostNumber` TEXT NOT NULL,
+        FOREIGN KEY(`host`) REFERENCES `host_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `host_2_idx` ON `host_2_cache`(`host`);
+
+    -- FIXME: this does not work as entries are never removed from the cache
+    CREATE TABLE IF NOT EXISTS `netgroup_cache`
+      ( `cn` TEXT NOT NULL,
+        `member` TEXT NOT NULL,
+        `mtime` TIMESTAMP NOT NULL,
+        UNIQUE (`cn`, `member`) );
+
+    -- tables for network cache
+    CREATE TABLE IF NOT EXISTS `network_cache`
+      ( `cn` TEXT PRIMARY KEY COLLATE NOCASE,
+        `mtime` TIMESTAMP NOT NULL );
+    CREATE TABLE IF NOT EXISTS `network_1_cache`
+      ( `network` TEXT NOT NULL COLLATE NOCASE,
+        `cn` TEXT NOT NULL COLLATE NOCASE,
+        FOREIGN KEY(`network`) REFERENCES `network_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `network_1_idx` ON `network_1_cache`(`network`);
+    CREATE TABLE IF NOT EXISTS `network_2_cache`
+      ( `network` TEXT NOT NULL,
+        `ipNetworkNumber` TEXT NOT NULL,
+        FOREIGN KEY(`network`) REFERENCES `network_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `network_2_idx` ON `network_2_cache`(`network`);
+
+    -- table for passwd cache
+    CREATE TABLE IF NOT EXISTS `passwd_cache`
+      ( `uid` TEXT PRIMARY KEY,
+        `userPassword` TEXT,
+        `uidNumber` INTEGER NOT NULL UNIQUE,
+        `gidNumber` INTEGER NOT NULL,
+        `gecos` TEXT,
+        `homeDirectory` TEXT,
+        `loginShell` TEXT,
+        `mtime` TIMESTAMP NOT NULL );
+
+    -- table for protocol cache
+    CREATE TABLE IF NOT EXISTS `protocol_cache`
+      ( `cn` TEXT PRIMARY KEY,
+        `ipProtocolNumber` INTEGER NOT NULL,
+        `mtime` TIMESTAMP NOT NULL );
+    CREATE TABLE IF NOT EXISTS `protocol_1_cache`
+      ( `protocol` TEXT NOT NULL,
+        `cn` TEXT NOT NULL,
+        FOREIGN KEY(`protocol`) REFERENCES `protocol_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `protocol_1_idx` ON `protocol_1_cache`(`protocol`);
+
+    -- table for rpc cache
+    CREATE TABLE IF NOT EXISTS `rpc_cache`
+      ( `cn` TEXT PRIMARY KEY,
+        `oncRpcNumber` INTEGER NOT NULL,
+        `mtime` TIMESTAMP NOT NULL );
+    CREATE TABLE IF NOT EXISTS `rpc_1_cache`
+      ( `rpc` TEXT NOT NULL,
+        `cn` TEXT NOT NULL,
+        FOREIGN KEY(`rpc`) REFERENCES `rpc_cache`(`cn`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `rpc_1_idx` ON `rpc_1_cache`(`rpc`);
+
+    -- tables for service cache
+    CREATE TABLE IF NOT EXISTS `service_cache`
+      ( `cn` TEXT NOT NULL,
+        `ipServicePort` INTEGER NOT NULL,
+        `ipServiceProtocol` TEXT NOT NULL,
+        `mtime` TIMESTAMP NOT NULL,
+        UNIQUE (`ipServicePort`, `ipServiceProtocol`) );
+    CREATE TABLE IF NOT EXISTS `service_1_cache`
+      ( `ipServicePort` INTEGER NOT NULL,
+        `ipServiceProtocol` TEXT NOT NULL,
+        `cn` TEXT NOT NULL,
+        FOREIGN KEY(`ipServicePort`) REFERENCES `service_cache`(`ipServicePort`)
+        ON DELETE CASCADE ON UPDATE CASCADE,
+        FOREIGN KEY(`ipServiceProtocol`) REFERENCES `service_cache`(`ipServiceProtocol`)
+        ON DELETE CASCADE ON UPDATE CASCADE );
+    CREATE INDEX IF NOT EXISTS `service_1_idx1` ON `service_1_cache`(`ipServicePort`);
+    CREATE INDEX IF NOT EXISTS `service_1_idx2` ON `service_1_cache`(`ipServiceProtocol`);
+
+    -- table for shadow cache
+    CREATE TABLE IF NOT EXISTS `shadow_cache`
+      ( `uid` TEXT PRIMARY KEY,
+        `userPassword` TEXT,
+        `shadowLastChange` INTEGER,
+        `shadowMin` INTEGER,
+        `shadowMax` INTEGER,
+        `shadowWarning` INTEGER,
+        `shadowInactive` INTEGER,
+        `shadowExpire` INTEGER,
+        `shadowFlag` INTEGER,
+        `mtime` TIMESTAMP NOT NULL );
+
+    ''')
+
+
+class Query(object):
+
+    def __init__(self, query, parameters=None):
+        self.query = query
+        self.wheres = []
+        self.parameters = []
+        if parameters:
+            for k, v in parameters.items():
+                self.add_where('`%s` = ?' % k, [v])
+
+    def add_query(self, query):
+        self.query += ' ' + query
+
+    def add_where(self, where, parameters):
+        self.wheres.append(where)
+        self.parameters += parameters
+
+    def execute(self, con):
+        query = self.query
+        if self.wheres:
+            query += ' WHERE ' + ' AND '.join(self.wheres)
+        c = con.cursor()
+        return c.execute(query, self.parameters)
+
+
+class CnAliasedQuery(Query):
+
+    sql = '''
+        SELECT `%(table)s_cache`.*,
+               `%(table)s_1_cache`.`cn` AS `alias`
+        FROM `%(table)s_cache`
+        LEFT JOIN `%(table)s_1_cache`
+          ON `%(table)s_1_cache`.`%(table)s` = `%(table)s_cache`.`cn`
+        '''
+
+    cn_join = '''
+        LEFT JOIN `%(table)s_1_cache` `cn_alias`
+          ON `cn_alias`.`%(table)s` = `%(table)s_cache`.`cn`
+        '''
+
+    def __init__(self, table, parameters):
+        args = dict(table=table)
+        super(CnAliasedQuery, self).__init__(self.sql % args)
+        for k, v in parameters.items():
+            if k == 'cn':
+                self.add_query(self.cn_join % args)
+                self.add_where('(`%(table)s_cache`.`cn` = ? OR `cn_alias`.`cn` = ?)' % args, [v, v])
+            else:
+                self.add_where('`%s` = ?' % k, [v])
+
+
+class RowGrouper(object):
+    """Pass in query results and group the results by a certain specified
+    list of columns."""
+
+    def __init__(self, results, groupby, columns):
+        self.groupby = groupby
+        self.columns = columns
+        self.results = itertools.groupby(results, key=self.keyfunc)
+
+    def __iter__(self):
+        return self
+
+    def keyfunc(self, row):
+        return tuple(row[x] for x in self.groupby)
+
+    def next(self):
+        groupcols, rows = self.results.next()
+        tmp = dict((x, list()) for x in self.columns)
+        for row in rows:
+            for col in self.columns:
+                if row[col] is not None:
+                    tmp[col].append(row[col])
+        result = dict(row)
+        result.update(tmp)
+        return result
+
+
+class Cache(object):
+
+    def __init__(self):
+        self.con = con
+        self.table = sys.modules[self.__module__].__name__
+
+    def store(self, *values):
+        """Store the values in the cache for the specified table."""
+        simple_values = []
+        multi_values = {}
+        for n, v in enumerate(values):
+            if isinstance(v, (list, tuple, set)):
+                multi_values[n] = v
+            else:
+                simple_values.append(v)
+        simple_values.append(datetime.datetime.now())
+        args = ', '.join(len(simple_values) * ('?', ))
+        con.execute('''
+            INSERT OR REPLACE INTO %s_cache
+            VALUES
+              (%s)
+            ''' % (self.table, args), simple_values)
+        for n, vlist in multi_values.items():
+            con.execute('''
+                DELETE FROM %s_%d_cache
+                WHERE `%s` = ?
+                ''' % (self.table, n, self.table), (values[0], ))
+            con.executemany('''
+                INSERT INTO %s_%d_cache
+                VALUES
+                  (?, ?)
+                ''' % (self.table, n), ((values[0], x) for x in vlist))
+
+    def retrieve(self, parameters):
+        """Retrieve all items from the cache based on the parameters supplied."""
+        query = Query('''
+            SELECT *
+            FROM %s_cache
+            ''' % self.table, parameters)
+        return (list(x)[:-1] for x in query.execute(self.con))