Changes to add duration into history database.

chrome/browser/history/history_database.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/history/history_database.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 
@@ skipping 10 matching lines @@
 #include "base/mac/mac_util.h"
 #endif
 
 namespace history {
 
 namespace {
 
 // Current version number. We write databases at the "current" version number,
 // but any previous version that can read the "compatible" one can make do with
 // or database without *too* many bad effects.
-static const int kCurrentVersionNumber = 20;
+static const int kCurrentVersionNumber = 21;
 static const int kCompatibleVersionNumber = 16;
 static const char kEarlyExpirationThresholdKey[] = "early_expiration_threshold";
 
 // Key in the meta table used to determine if we need to migrate thumbnails out
 // of history.
 static const char kNeedsThumbnailMigrationKey[] = "needs_thumbnail_migration";
 
 void ComputeDatabaseMetrics(const FilePath& history_name,
                             sql::Connection& db) {
   if (base::RandInt(1, 100) != 50)
@@ skipping 258 matching lines @@
   }
 
   if (cur_version == 19) {
     cur_version++;
     meta_table_.SetVersionNumber(cur_version);
     // Set a key indicating we need to migrate thumbnails. When successfull the
     // key is removed (ThumbnailMigrationDone).
     meta_table_.SetValue(kNeedsThumbnailMigrationKey, 1);
   }
 
+  if (cur_version == 20) {
+    // This is the version prior to adding the visit_duration field in visits
+    // database. We need to migrate the database.
+    if (!MigrateVisitsWithoutDuration()) {
+      LOG(WARNING) << "Unable to update history database to version 21.";
+      return sql::INIT_FAILURE;
+    }
+    ++cur_version;
+    meta_table_.SetVersionNumber(cur_version);
+  }
+
   // When the version is too old, we just try to continue anyway, there should
   // not be a released product that makes a database too old for us to handle.
   LOG_IF(WARNING, cur_version < GetCurrentVersion()) <<
          "History database version " << cur_version << " is too old to handle.";
 
   return sql::INIT_OK;
 }
 
 #if !defined(OS_WIN)
 void HistoryDatabase::MigrateTimeEpoch() {
@@ skipping 14 matching lines @@
       "WHERE id IN (SELECT id FROM segment_usage WHERE time_slot > 0);"));
 
   // Erase all the full text index files. These will take a while to update and
   // are less important, so we just blow them away. Same with the archived
   // database.
   needs_version_17_migration_ = true;
 }
 #endif
 
 }  // namespace history