snippets for working with indexeddb object stores

idb-samples.js

exports.getLowerBounds = function()
{
  var openReq = indexedDB.open( databaseName )
  
  openReq.onsuccess = function( e )
  {
    var idb = e.target.result
    var transaction = idb.transaction( objectStoreName, "readonly" )
    var objectStore = transaction.objectStore( objectStoreName )
    var keyRangeValue = IDBKeyRange.lowerBound( 18 )
    var openCursorRequest = objectStore.openCursor( keyRangeValue )

    openCursorRequest.onsuccess = function( event )
    {
      var cursor = event.target.result
      if ( cursor ) {
        console.log( cursor.value )
        cursor.continue()
      } else {
        console.log( "Entries all displayed." )
      }
    }
  }
}

exports.getLatest = function()
{
  var openReq = indexedDB.open( databaseName )
  
  openReq.onsuccess = function( e )
  {
    var idb = e.target.result
    var transaction = idb.transaction( objectStoreName, "readonly" )
    var objectStore = transaction.objectStore( objectStoreName )
    var openCursorRequest = objectStore.openCursor( null, "prev" )

    openCursorRequest.onsuccess = function( event )
    {
      var cursor = event.target.result
      if ( cursor ) {
        console.log( cursor.value )
      } else {
        console.log( "Entries all displayed." )
      }
    }
  }
}