diff --git a/gajim/common/logger.py b/gajim/common/logger.py
index d35fd6083..e2de43c95 100644
--- a/gajim/common/logger.py
+++ b/gajim/common/logger.py
@@ -1174,6 +1174,88 @@ class Logger:
         self.write(type_, with_, message=msg, tim=tim,
                    additional_data=additional_data, mam_query=True)
 
+    def search_for_duplicate(self, jid, timestamp, msg):
+        """
+        Check if a message is already in the `logs` table
+
+        :param jid:         The jid as string
+
+        :param timestamp:   The timestamp in UTC epoch
+
+        :param msg:         The message text
+        """
+
+        # Add 5 minutes around the timestamp
+        start_time = timestamp - 300
+        end_time = timestamp + 300
+
+        log.debug('start: %s, end: %s, jid: %s, message: %s',
+                  start_time, end_time, jid, msg)
+
+        sql = '''
+            SELECT * FROM logs
+            NATURAL JOIN jids WHERE jid = ? AND message = ?
+            AND time BETWEEN ? AND ?
+            '''
+
+        result = self.con.execute(sql, (jid, msg, start_time, end_time)).fetchone()
+
+        if result is not None:
+            log.debug('Message already in DB')
+            return True
+        return False
+
+    def insert_jid(self, jid, kind=None, type_=JIDConstant.NORMAL_TYPE):
+        """
+        Insert a new jid into the `jids` table.
+
+        :param jid:     The jid as string
+
+        :param kind:    A KindConstant
+
+        :param type_:   A JIDConstant
+        """
+        if kind == KindConstant.GC_MSG:
+            type_ = JIDConstant.ROOM_TYPE
+        sql = 'INSERT OR IGNORE INTO jids (jid, type) VALUES (?, ?)'
+        self.con.execute(sql, (jid, type_))
+        self._timeout_commit()
+
+    def insert_into_logs(self, jid, time_, kind, unread=True, **kwargs):
+        """
+        Insert a new message into the `logs` table
+
+        :param jid:     The jid as string
+
+        :param time_:   The timestamp in UTC epoch
+
+        :param kind:    A KindConstant
+
+        :param unread:  If True the message is added to the`unread_messages`
+                        table. Only if kind == CHAT_MSG_RECV
+
+        :param kwargs:  Every additional named argument must correspond to
+                        a field in the `logs` table
+        """
+        self.insert_jid(jid, kind=kind)
+
+        sql = '''
+              INSERT INTO logs (jid_id, time, kind, {columns})
+              VALUES ((SELECT jid_id FROM jids WHERE jid = ?), ?, ?, {values})
+              '''.format(columns=', '.join(kwargs.keys()),
+                         values=', '.join('?' * len(kwargs)))
+
+        lastrowid = self.con.execute(sql, (jid, time_, kind, *kwargs.values())).lastrowid
+
+        if unread and kind == KindConstant.CHAT_MSG_RECV:
+            sql = '''INSERT INTO unread_messages (message_id, jid_id)
+                     VALUES (?, (SELECT jid_id FROM jids WHERE jid = ?))'''
+            self.con.execute(sql, (lastrowid, jid))
+
+        self._timeout_commit()
+
+        return lastrowid
+
     def _nec_gc_message_received(self, obj):
         tim_f = float(obj.timestamp)
         tim_int = int(tim_f)