--- a/SqliteDBLink.cpp	Tue Oct 22 14:22:00 2013 +0200
+++ b/SqliteDBLink.cpp	Tue Oct 22 14:40:08 2013 +0200
@@ -294,7 +294,7 @@
   checksums.clear();
 }
 
-bool SqliteDBLink::commit()
+bool SqliteDBLink::commit(const QString& prefix)
 {
   OperationType last = None;
   QVariantList paths, sizes, mtimes, hashes;
@@ -321,8 +321,18 @@
   }
 
   QSqlQuery whatToUpdate(db);
-  whatToUpdate.prepare("SELECT path FROM files WHERE checksum is NULL AND size in (SELECT size FROM files WHERE size <> 0 GROUP BY size HAVING count(*) > 1 ORDER BY SIZE) ORDER BY size");
-
+  QString whatToUpdateQuery = "SELECT path FROM files WHERE checksum is NULL AND size in (SELECT size FROM files WHERE size <> 0 GROUP BY size HAVING count(*) > 1 ORDER BY SIZE) %1 ORDER BY size";
+  if (prefix.isEmpty()) {
+    whatToUpdateQuery = whatToUpdateQuery.arg("");
+  }
+  else {
+    whatToUpdateQuery = whatToUpdateQuery.arg("AND path LIKE :prefix");
+  }
+  whatToUpdate.prepare(whatToUpdateQuery);
+  if (!prefix.isEmpty()) {
+    whatToUpdate.bindValue("prefix", QString("%1%").arg(prefix));
+  }
+  
   if (!whatToUpdate.exec()) {
     throw SQLException(whatToUpdate);
   }