--- a/storage/src/mozStorageConnection.cpp
+++ b/storage/src/mozStorageConnection.cpp
@@ -699,17 +699,19 @@ Connection::initializeInternal(nsIFile* 
 
 nsresult
 Connection::databaseElementExists(enum DatabaseElementType aElementType,
                                   const nsACString &aElementName,
                                   bool *_exists)
 {
   if (!mDBConn) return NS_ERROR_NOT_INITIALIZED;
 
-  nsAutoCString query("SELECT name FROM sqlite_master WHERE type = '");
+  nsCString query("SELECT name FROM (SELECT * FROM sqlite_master UNION ALL "
+                                    "SELECT * FROM sqlite_temp_master) "
+                  "WHERE type = '");
   switch (aElementType) {
     case INDEX:
       query.Append("index");
       break;
     case TABLE:
       query.Append("table");
       break;
   }

--- a/storage/test/unit/test_storage_connection.js
+++ b/storage/test/unit/test_storage_connection.js
@@ -103,16 +103,29 @@ add_task(function test_tableExists_not_c
 });
 
 add_task(function test_indexExists_not_created()
 {
   var msc = getOpenedDatabase();
   do_check_false(msc.indexExists("foo"));
 });
 
+add_task(function test_temp_tableExists_and_indexExists()
+{
+  var msc = getOpenedDatabase();
+  msc.executeSimpleSQL("CREATE TEMP TABLE test_temp(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT)");
+  do_check_true(msc.tableExists("test_temp"));
+
+  msc.executeSimpleSQL("CREATE INDEX test_temp_ind ON test_temp (name)");
+  do_check_true(msc.indexExists("test_temp_ind"));
+
+  msc.executeSimpleSQL("DROP INDEX test_temp_ind");
+  msc.executeSimpleSQL("DROP TABLE test_temp");
+});
+
 add_task(function test_createTable_not_created()
 {
   var msc = getOpenedDatabase();
   msc.createTable("test", "id INTEGER PRIMARY KEY, name TEXT");
   do_check_true(msc.tableExists("test"));
 });
 
 add_task(function test_indexExists_created()

--- a/toolkit/modules/Sqlite.jsm
+++ b/toolkit/modules/Sqlite.jsm
@@ -595,48 +595,48 @@ OpenedConnection.prototype = Object.free
         deferred.reject(error);
       }.bind(this)
     );
 
     return deferred.promise;
   },
 
   /**
-   * Whether a table exists in the database.
-   *
-   * IMPROVEMENT: Look for temporary tables.
+   * Whether a table exists in the database (both persistent and temporary tables).
    *
    * @param name
    *        (string) Name of the table.
    *
    * @return Promise<bool>
    */
   tableExists: function (name) {
     return this.execute(
-      "SELECT name FROM sqlite_master WHERE type='table' AND name=?",
+      "SELECT name FROM (SELECT * FROM sqlite_master UNION ALL " +
+                        "SELECT * FROM sqlite_temp_master) " +
+      "WHERE type = 'table' AND name=?",
       [name])
       .then(function onResult(rows) {
         return Promise.resolve(rows.length > 0);
       }
     );
   },
 
   /**
-   * Whether a named index exists.
-   *
-   * IMPROVEMENT: Look for indexes in temporary tables.
+   * Whether a named index exists (both persistent and temporary tables).
    *
    * @param name
    *        (string) Name of the index.
    *
    * @return Promise<bool>
    */
   indexExists: function (name) {
     return this.execute(
-      "SELECT name FROM sqlite_master WHERE type='index' AND name=?",
+      "SELECT name FROM (SELECT * FROM sqlite_master UNION ALL " +
+                        "SELECT * FROM sqlite_temp_master) " +
+      "WHERE type = 'index' AND name=?",
       [name])
       .then(function onResult(rows) {
         return Promise.resolve(rows.length > 0);
       }
     );
   },
 
   /**

--- a/toolkit/modules/tests/xpcshell/test_sqlite.js
+++ b/toolkit/modules/tests/xpcshell/test_sqlite.js
@@ -55,16 +55,32 @@ function getDummyDatabase(name, extraOpt
   for (let [k, v] in Iterator(TABLES)) {
     yield c.execute("CREATE TABLE " + k + "(" + v + ")");
     c._initialStatementCount++;
   }
 
   throw new Task.Result(c);
 }
 
+function getDummyTempDatabase(name, extraOptions={}) {
+  const TABLES = {
+    dirs: "id INTEGER PRIMARY KEY AUTOINCREMENT, path TEXT",
+    files: "id INTEGER PRIMARY KEY AUTOINCREMENT, dir_id INTEGER, path TEXT",
+  };
+
+  let c = yield getConnection(name, extraOptions);
+  c._initialStatementCount = 0;
+
+  for (let [k, v] in Iterator(TABLES)) {
+    yield c.execute("CREATE TEMP TABLE " + k + "(" + v + ")");
+    c._initialStatementCount++;
+  }
+
+  throw new Task.Result(c);
+}
 
 function run_test() {
   Cu.import("resource://testing-common/services-common/logging.js");
   initTestLogging("Trace");
 
   run_next_test();
 }
 
@@ -198,16 +214,37 @@ add_task(function test_index_exists() {
   do_check_false(yield c.indexExists("does_not_exist"));
 
   yield c.execute("CREATE INDEX my_index ON dirs (path)");
   do_check_true(yield c.indexExists("my_index"));
 
   yield c.close();
 });
 
+add_task(function test_temp_table_exists() {
+  let c = yield getDummyTempDatabase("temp_table_exists");
+
+  do_check_false(yield c.tableExists("temp_does_not_exist"));
+  do_check_true(yield c.tableExists("dirs"));
+  do_check_true(yield c.tableExists("files"));
+
+  yield c.close();
+});
+
+add_task(function test_temp_index_exists() {
+  let c = yield getDummyTempDatabase("temp_index_exists");
+
+  do_check_false(yield c.indexExists("temp_does_not_exist"));
+
+  yield c.execute("CREATE INDEX my_index ON dirs (path)");
+  do_check_true(yield c.indexExists("my_index"));
+
+  yield c.close();
+});
+
 add_task(function test_close_cached() {
   let c = yield getDummyDatabase("close_cached");
 
   yield c.executeCached("SELECT * FROM dirs");
   yield c.executeCached("SELECT * FROM files");
 
   yield c.close();
 });