diff --git a/src/daemon/db-mgr.cpp b/src/daemon/db-mgr.cpp
index b925f2d..5652de2 100644
--- a/src/daemon/db-mgr.cpp
+++ b/src/daemon/db-mgr.cpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2017, Regents of the University of California.
+ * Copyright (c) 2014-2018, Regents of the University of California.
  *
  * This file is part of NDNS (Named Data Networking Domain Name Service).
  * See AUTHORS.md for complete list of NDNS authors and contributors.
@@ -125,6 +125,37 @@
   NDNS_LOG_INFO("clear all the data in the database: " << m_dbFile);
 }
 
+
+void
+DbMgr::saveName(const Name& name, sqlite3_stmt* stmt, int iCol, bool isStatic)
+{
+  const Block& wire = name.wireEncode();
+  sqlite3_bind_blob(stmt, iCol, wire.value(), wire.value_size(), isStatic ? SQLITE_STATIC : SQLITE_TRANSIENT);
+}
+
+Name
+DbMgr::restoreName(sqlite3_stmt* stmt, int iCol)
+{
+  Name name;
+
+  const uint8_t* buffer = static_cast<const uint8_t*>(sqlite3_column_blob(stmt, iCol));
+  size_t nBytesLeft = sqlite3_column_bytes(stmt, iCol);
+
+  while (nBytesLeft > 0) {
+    bool hasDecodingSucceeded;
+    name::Component component;
+    std::tie(hasDecodingSucceeded, component) = Block::fromBuffer(buffer, nBytesLeft);
+    if (!hasDecodingSucceeded) {
+      BOOST_THROW_EXCEPTION(Error("Error while decoding name from the database"));
+    }
+    name.append(component);
+    buffer += component.size();
+    nBytesLeft -= component.size();
+  }
+
+  return name;
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 // Zone
 ///////////////////////////////////////////////////////////////////////////////////////////////////
@@ -142,8 +173,8 @@
     BOOST_THROW_EXCEPTION(PrepareError(sql));
   }
 
-  const Block& zoneName = zone.getName().wireEncode();
-  sqlite3_bind_blob(stmt, 1, zoneName.wire(), zoneName.size(), SQLITE_STATIC);
+
+  saveName(zone.getName(), stmt, 1);
   sqlite3_bind_int(stmt,  2, zone.getTtl().count());
 
   rc = sqlite3_step(stmt);
@@ -233,8 +264,7 @@
     BOOST_THROW_EXCEPTION(PrepareError(sql));
   }
 
-  const Block& zoneName = zone.getName().wireEncode();
-  sqlite3_bind_blob(stmt, 1, zoneName.wire(), zoneName.size(), SQLITE_STATIC);
+  saveName(zone.getName(), stmt, 1);
 
   if (sqlite3_step(stmt) == SQLITE_ROW) {
     zone.setId(sqlite3_column_int64(stmt, 0));
@@ -266,8 +296,7 @@
     Zone& zone = vec.back();
     zone.setId(sqlite3_column_int64(stmt, 0));
     zone.setTtl(time::seconds(sqlite3_column_int(stmt, 2)));
-    zone.setName(Name(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 1)),
-                            sqlite3_column_bytes(stmt, 1))));
+    zone.setName(restoreName(stmt, 1));
   }
   sqlite3_finalize(stmt);
 
@@ -331,8 +360,7 @@
 
   sqlite3_bind_int64(stmt, 1, rrset.getZone()->getId());
 
-  const Block& label = rrset.getLabel().wireEncode();
-  sqlite3_bind_blob(stmt,  2, label.wire(),              label.size(),              SQLITE_STATIC);
+  saveName(rrset.getLabel(), stmt, 2);
   sqlite3_bind_blob(stmt,  3, rrset.getType().wire(),    rrset.getType().size(),    SQLITE_STATIC);
   sqlite3_bind_blob(stmt,  4, rrset.getVersion().wire(), rrset.getVersion().size(), SQLITE_STATIC);
   sqlite3_bind_int64(stmt, 5, rrset.getTtl().count());
@@ -374,8 +402,52 @@
 
   sqlite3_bind_int64(stmt, 1, rrset.getZone()->getId());
 
-  const Block& label = rrset.getLabel().wireEncode();
-  sqlite3_bind_blob(stmt, 2, label.wire(), label.size(), SQLITE_STATIC);
+  saveName(rrset.getLabel(), stmt, 2);
+  sqlite3_bind_blob(stmt, 3, rrset.getType().wire(), rrset.getType().size(), SQLITE_STATIC);
+
+  if (sqlite3_step(stmt) == SQLITE_ROW) {
+    rrset.setId(sqlite3_column_int64(stmt, 0));
+    rrset.setTtl(time::seconds(sqlite3_column_int64(stmt, 1)));
+    rrset.setVersion(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 2)),
+                           sqlite3_column_bytes(stmt, 2)));
+    rrset.setData(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
+                        sqlite3_column_bytes(stmt, 3)));
+  }
+  else {
+    rrset.setId(0);
+  }
+  sqlite3_finalize(stmt);
+
+  return rrset.getId() != 0;
+}
+
+bool
+DbMgr::findLowerBound(Rrset& rrset)
+{
+  if (rrset.getZone() == 0) {
+    BOOST_THROW_EXCEPTION(RrsetError("Rrset has not been assigned to a zone"));
+  }
+
+  if (rrset.getZone()->getId() == 0) {
+    bool isFound = find(*rrset.getZone());
+    if (!isFound) {
+      return false;
+    }
+  }
+
+  sqlite3_stmt* stmt;
+  const char* sql =
+    "SELECT id, ttl, version, data FROM rrsets"
+    "    WHERE zone_id=? and label<? and type=? ORDER BY label DESC";
+  int rc = sqlite3_prepare_v2(m_conn, sql, -1, &stmt, 0);
+
+  if (rc != SQLITE_OK) {
+    BOOST_THROW_EXCEPTION(PrepareError(sql));
+  }
+
+  sqlite3_bind_int64(stmt, 1, rrset.getZone()->getId());
+
+  saveName(rrset.getLabel(), stmt, 2);
   sqlite3_bind_blob(stmt, 3, rrset.getType().wire(), rrset.getType().size(), SQLITE_STATIC);
 
   if (sqlite3_step(stmt) == SQLITE_ROW) {
@@ -406,7 +478,7 @@
   std::vector<Rrset> vec;
   sqlite3_stmt* stmt;
   const char* sql = "SELECT id, ttl, version, data, label, type "
-                    "FROM rrsets where zone_id=? ";
+                    "FROM rrsets where zone_id=? ORDER BY label";
 
   int rc = sqlite3_prepare_v2(m_conn, sql, -1, &stmt, 0);
   if (rc != SQLITE_OK) {
@@ -424,8 +496,7 @@
                            sqlite3_column_bytes(stmt, 2)));
     rrset.setData(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 3)),
                         sqlite3_column_bytes(stmt, 3)));
-    rrset.setLabel(Name(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 4)),
-                         sqlite3_column_bytes(stmt, 4))));
+    rrset.setLabel(restoreName(stmt, 4));
     rrset.setType(Block(static_cast<const uint8_t*>(sqlite3_column_blob(stmt, 5)),
                   sqlite3_column_bytes(stmt, 5)));
   }
@@ -434,6 +505,33 @@
   return vec;
 }
 
+void
+DbMgr::removeRrsetsOfZoneByType(Zone& zone, const name::Component& type)
+{
+  if (zone.getId() == 0)
+    find(zone);
+
+  if (zone.getId() == 0)
+    BOOST_THROW_EXCEPTION(RrsetError("Attempting to find all the rrsets with a zone does not in the database"));
+
+  sqlite3_stmt* stmt;
+  const char* sql = "DELETE FROM rrsets WHERE zone_id = ? AND type = ?";
+  int rc = sqlite3_prepare_v2(m_conn, sql, -1, &stmt, 0);
+
+  if (rc != SQLITE_OK) {
+    BOOST_THROW_EXCEPTION(PrepareError(sql));
+  }
+
+  sqlite3_bind_int64(stmt, 1, zone.getId());
+  sqlite3_bind_blob(stmt,  2, type.wire(), type.size(), SQLITE_STATIC);
+
+  rc = sqlite3_step(stmt);
+  if (rc != SQLITE_DONE) {
+    sqlite3_finalize(stmt);
+    BOOST_THROW_EXCEPTION(ExecuteError(sql));
+  }
+  sqlite3_finalize(stmt);
+}
 
 void
 DbMgr::remove(Rrset& rrset)