--- a/sat/memory/sqlite.py	Mon Dec 10 21:06:20 2018 +0100
+++ b/sat/memory/sqlite.py	Tue Dec 11 23:53:27 2018 +0100
@@ -1193,6 +1193,30 @@
     def update_v7(self):
         """Update database from v6 to v7 (history unique constraint change)"""
         log.info(u"Database update to v7, this may take a while")
+
+        log.info(u"some cleaning first")
+        # we need to fix duplicate stanza_id, as it can result in conflicts with the new schema
+        # normally database should not contain any, but better safe than sorry.
+        rows = yield self.dbpool.runQuery(
+            u"SELECT stanza_id, COUNT(*) as c FROM history WHERE stanza_id is not NULL "
+            u"GROUP BY stanza_id HAVING c>1")
+        if rows:
+            count = sum([r[1] for r in rows]) - len(rows)
+            log.info(u"{count} duplicate stanzas found, cleaning".format(count=count))
+            for stanza_id, count in rows:
+                log.info(u"cleaning duplicate stanza {stanza_id}".format(stanza_id=stanza_id))
+                row_uids = yield self.dbpool.runQuery(
+                    "SELECT uid FROM history WHERE stanza_id = ? LIMIT ?",
+                    (stanza_id, count-1))
+                uids = [r[0] for r in row_uids]
+                yield self.dbpool.runQuery(
+                    "DELETE FROM history WHERE uid IN ({})".format(u",".join(u"?"*len(uids))),
+                    uids)
+
+        log.info(u'Deleting "info" messages (this can take a while, please be patient)')
+        yield self.dbpool.runQuery(u"DELETE FROM history where type='info'");
+        log.info(u"Cleaning done")
+
         # we have to rename table we will replace
         # tables referencing history need to be replaced to, else reference would
         # be to the old table (which will be dropped at the end). This buggy behaviour
@@ -1202,25 +1226,6 @@
         yield self.dbpool.runQuery("ALTER TABLE subject RENAME TO subject_old")
         yield self.dbpool.runQuery("ALTER TABLE thread RENAME TO thread_old")
 
-        # we need to fix duplicate stanza_id, as it can result in conflicts with the new schema
-        # normally database should not contain any, but better safe than sorry.
-        rows = yield self.dbpool.runQuery(
-            u"SELECT stanza_id, COUNT(*) as c FROM history_old WHERE stanza_id is not NULL "
-            u"GROUP BY stanza_id HAVING c>1")
-        if rows:
-            count = sum([r[1] for r in rows]) - len(rows)
-            log.info(u"{count} duplicate stanzas found, cleaning".format(count=count))
-            for stanza_id, count in rows:
-                log.info(u"cleaning duplicate stanza {stanza_id}".format(stanza_id=stanza_id))
-                row_uids = yield self.dbpool.runQuery(
-                    "SELECT uid FROM history_old WHERE stanza_id = ? LIMIT ?",
-                    (stanza_id, count-1))
-                uids = [r[0] for r in row_uids]
-                yield self.dbpool.runQuery(
-                    "DELETE FROM history_old WHERE uid IN ({})".format(u",".join(u"?"*len(uids))),
-                    uids)
-            log.info(u"Cleaning done")
-
         # history
         query = (u"CREATE TABLE history (uid TEXT PRIMARY KEY, stanza_id TEXT, "
                  u"update_uid TEXT, profile_id INTEGER, source TEXT, dest TEXT, "
@@ -1249,8 +1254,7 @@
                  u"history(uid) ON DELETE CASCADE)")
         yield self.dbpool.runQuery(query)
 
-        log.info(u"Now transfering old data to new tables, this can be really long "
-                 u"depending on your history size, please be patient.")
+        log.info(u"Now transfering old data to new tables, please be patient.")
 
         log.info(u"\nTransfering table history")
         query = (u"INSERT INTO history (uid, stanza_id, update_uid, profile_id, source, "
@@ -1275,10 +1279,12 @@
                  u", history_uid, thread_id, parent_id FROM thread_old")
         yield self.dbpool.runQuery(query)
 
-        yield self.dbpool.runQuery("DROP TABLE history_old")
+        # because of foreign keys, tables referencing history_old
+        # must be deleted first
+        yield self.dbpool.runQuery("DROP TABLE thread_old")
+        yield self.dbpool.runQuery("DROP TABLE subject_old")
         yield self.dbpool.runQuery("DROP TABLE message_old")
-        yield self.dbpool.runQuery("DROP TABLE subject_old")
-        yield self.dbpool.runQuery("DROP TABLE thread_old")
+        yield self.dbpool.runQuery("DROP TABLE history_old")
         log.info(u"Database update done :)")
 
     @defer.inlineCallbacks