Index: CHANGES.txt
===================================================================
--- CHANGES.txt	(revision 1703325)
+++ CHANGES.txt	(working copy)
@@ -2,6 +2,8 @@
 
 Current Development 2.4-SNAPSHOT
 
+* NUTCH-1679 UpdateDb using batchId, link may override crawled page (Tien Nguyen Manh, Koen Smets, Alfonso Nishikawa, Alexander Kingson via lewismc)
+
 * NUTCH-2077 Upgrade to Tika 1.10 (Michael Joyce, lewismc)
 
 * NUTCH-2045 index-basic incorrect assignment of next fetch time (page.getFetchTime()) as page fetch time (lewismc)
Index: src/java/org/apache/nutch/crawl/DbUpdateReducer.java
===================================================================
--- src/java/org/apache/nutch/crawl/DbUpdateReducer.java	(revision 1703325)
+++ src/java/org/apache/nutch/crawl/DbUpdateReducer.java	(working copy)
@@ -35,10 +35,12 @@
 import org.apache.nutch.storage.WebPage;
 import org.apache.nutch.util.TableUtil;
 import org.apache.nutch.util.WebPageWritable;
+import org.apache.nutch.storage.StorageUtils;
+import org.apache.gora.store.DataStore;
 import org.slf4j.Logger;
 
 public class DbUpdateReducer extends
-    GoraReducer<UrlWithScore, NutchWritable, String, WebPage> {
+GoraReducer<UrlWithScore, NutchWritable, String, WebPage> {
 
   public static final String CRAWLDB_ADDITIONS_ALLOWED = "db.update.additions.allowed";
 
@@ -51,10 +53,11 @@
   private ScoringFilters scoringFilters;
   private List<ScoreDatum> inlinkedScoreData = new ArrayList<ScoreDatum>();
   private int maxLinks;
+  public DataStore<String, WebPage> datastore;
 
   @Override
   protected void setup(Context context) throws IOException,
-      InterruptedException {
+  InterruptedException {
     Configuration conf = context.getConfiguration();
     retryMax = conf.getInt("db.fetch.retry.max", 3);
     additionsAllowed = conf.getBoolean(CRAWLDB_ADDITIONS_ALLOWED, true);
@@ -62,7 +65,18 @@
     schedule = FetchScheduleFactory.getFetchSchedule(conf);
     scoringFilters = new ScoringFilters(conf);
     maxLinks = conf.getInt("db.update.max.inlinks", 10000);
+    try {
+      datastore = StorageUtils.createWebStore(conf, String.class, WebPage.class);
+    }
+    catch (ClassNotFoundException e) {
+      throw new IOException(e);
+    }
   }
+  
+  @Override
+  protected void cleanup(Context context) throws IOException, InterruptedException {
+    datastore.close();
+  }
 
   @Override
   protected void reduce(UrlWithScore key, Iterable<NutchWritable> values,
@@ -70,6 +84,8 @@
     String keyUrl = key.getUrl().toString();
 
     WebPage page = null;
+    //initialize old_page for checking if the outlink is already in the datastore
+    WebPage old_page = null;
     inlinkedScoreData.clear();
 
     for (NutchWritable nutchWritable : values) {
@@ -94,7 +110,12 @@
       return;
     }
 
-    if (page == null) { // new row
+    //check if page is already in the db
+    if(page == null && (old_page = datastore.get(keyUrl)) != null) { 
+      //if we return here inlinks will not be updated
+      page=old_page;
+    } 
+    else if (page == null) { //new row 
       if (!additionsAllowed) {
         return;
       }