mozilla
Your Search Results

    IDBObjectStore

    The IDBObjectStore interface of the IndexedDB API represents an object store in a database. Records within an object store are sorted according to their keys. This sorting enables fast insertion, look-up, and ordered retrieval.

    Methods

    IDBObjectStore.add
    Returns an IDBRequest object, and, in a separate thread, creates a structured clone of the value, and stores the cloned value in the object store. This is for adding new records to an object store.
    IDBObjectStore.clear
    Creates and immediately returns an IDBRequest object, and clears this object store in a separate thread. This is for deleting all current records out of an object store.
    IDBObjectStore.delete
    returns an IDBRequest object, and, in a separate thread, deletes the current object store. This is for deleting individual records out of an object store.
    IDBObjectStore.get
    returns an IDBRequest object, and, in a separate thread, returns the object store selected by the specified key. This is for retrieving specific records from an object store.
    IDBObjectStore.createIndex
    Creates a new index during a version upgrade, returning a new IDBIndex object in the connected database.
    IDBObjectStore.deleteIndex
    Destroys the specified index in the connected database, used during a version upgrade.
    IDBObjectStore.index
    Opens an index from this object store after which it can, for example, be used to return a sequence of records sorted by that index using a cursor.
    IDBObjectStore.put
    Returns an IDBRequest object, and, in a separate thread, creates a structured clone of the value, and stores the cloned value in the object store. This is for updating existing records in an object store when the transaction's mode is readwrite.
    IDBObjectStore.openCursor
    Returns an IDBRequest object, and, in a separate thread, returns a new IDBCursorWithValue object. Used for iterating through an object store by primary key with a cursor.
    IDBObjectStore.count
    Returns an IDBRequest object, and, in a separate thread, returns the total number of records that match the provided key or IDBKeyRange. If no arguments are provided, it returns the total number of records in the store.

    Properties

    IDBObjectStore.indexNames Read only
    A list of the names of indexes on objects in this object store.
    IDBObjectStore.keyPath Read only
    The key path of this object store. If this attribute is null, the application must provide a key for each modification operation.
    IDBObjectStore.name Read only
    The name of this object store.
    IDBObjectStore.transaction Read only
    The name of the transaction to which this object store belongs.
    IDBObjectStore.autoIncrement Read only
    The value of the auto increment flag for this object store.

    Obsolete methods

    IDBObjectStore.openKeyCursor 
    Returns an IDBRequest object, and, in a separate thread, returns a new IDBCursorWithValue. Used for iterating through an object store with a key. However, this is now handled by IDBObjectStore.openCursor, if a value is specified.

    Example

    This example shows a variety of different uses of ObjectStores, from updating the data structure with IDBObjectStore.createIndex inside an onupgradeneeded function, to adding a new item to our object store with IDBObjectStore.add. For a full working example, see our To-do Notifications app (view example live.)

    // Let us open our database
    var DBOpenRequest = window.indexedDB.open("toDoList", 4);
    
    DBOpenRequest.onsuccess = function(event) {
      note.innerHTML += '<li>Database initialised.</li>';
     
      // store the result of opening the database in the db variable.
      db = DBOpenRequest.result;
    };
    
    // This event handles the event whereby a new version of the database needs to be created
    // Either one has not been created before, or a new version number has been submitted via the
    // window.indexedDB.open line above
    DBOpenRequest.onupgradeneeded = function(event) {
      var db = event.target.result;
     
      db.onerror = function(event) {
        note.innerHTML += '<li>Error loading database.</li>';
      };
    
      // Create an objectStore for this database
     
      var objectStore = db.createObjectStore("toDoList", { keyPath: "taskTitle" });
     
      // define what data items the objectStore will contain
     
      objectStore.createIndex("hours", "hours", { unique: false });
      objectStore.createIndex("minutes", "minutes", { unique: false });
      objectStore.createIndex("day", "day", { unique: false });
      objectStore.createIndex("month", "month", { unique: false });
      objectStore.createIndex("year", "year", { unique: false });
    
      objectStore.createIndex("notified", "notified", { unique: false });
     
      note.innerHTML += '<li>Object store created.</li>';
    };
    
    // Create a new item to add in to the object store
    var newItem = [
      { taskTitle: "Walk dog", hours: 19, minutes: 30, day: 24, month: 'December', year: 2013, notified: "no" }
    ];
    
    // open a read/write db transaction, ready for adding the data
    var transaction = db.transaction(["toDoList"], "readwrite");
        
    // report on the success of opening the transaction
    transaction.oncomplete = function(event) {
      note.innerHTML += '<li>Transaction opened for task addition.</li>';
    };
    
    transaction.onerror = function(event) {
      note.innerHTML += '<li>Transaction not opened due to error. Duplicate items not allowed.</li>';
    };
    
    // create an object store on the transaction
    var objectStore = transaction.objectStore("toDoList");
    // add our newItem object to the object store
    var objectStoreRequest = objectStore.add(newItem[0]);        
    
    objectStoreRequest.onsuccess = function(event) {
      note.innerHTML += '<li>New item added to database.</li>';
    }

    Specifications

    Specification Status Comment
    Indexed Database API
    The definition of 'IDBObjectStore' in that specification.
    Candidate Recommendation  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
    Basic support 23webkit
    24
    10 moz
    16.0 (16.0)
    10, partial 15 7.1
    Feature Android Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile
    Basic support 4.4 22.0 (22.0) 1.0.1 10 22 Not supported

    See also

    Document Tags and Contributors

    Last updated by: chrisdavidmills,