Web/API/IDBCursor/continuePrimaryKey

The continuePrimaryKey() method of the IDBCursor interface advances the cursor to the to the item whose key matches the key parameter as well as whose primary key matches the primary key parameter.

A typical use case, is to resume the iteration where a previous cursor has been closed, without having to compare the keys one by one.

Calling this method more than once before new cursor data has been loaded - for example, calling continuePrimaryKey() twice from the same onsuccess handler - results in an InvalidStateError being thrown on the second call because the cursor’s got value flag has been unset.

This method is only valid for cursors coming from an index. Using it for cursors coming from an object store will throw an error.

Note: This feature is available in Web Workers.

Syntax

cursor.continuePrimaryKey(key, primaryKey);

Parameters

key: The key to position the cursor at.
primaryKey: The primary key to position the cursor at.

Exceptions

This method may raise a DOMException of one of the following types:

Exception	Description
`TransactionInactiveError`	This IDBCursor's transaction is inactive.
`DataError`	The key parameter may have any of the following conditions: The key is not a valid key. The key is less than or equal to this cursor's position and the cursor's direction is `next` or `nextunique`. The key is greater than or equal to this cursor's position and this cursor's direction is `prev` or `prevunique`.
`InvalidStateError`	The cursor is currently being iterated or has iterated past its end.
`InvalidAccessError`	The cursor's direction is not `prev` or `next`.

Example

here’s how you can resume an iteration of all articles tagged with "javascript" since your last visit:

let request = articleStore.index("tag").openCursor();
let count = 0;
let unreadList = [];
request.onsuccess = (event) => {
    let cursor = event.target.result;
    if (!cursor) { return; }
    let lastPrimaryKey = getLastIteratedArticleId();
    if (lastPrimaryKey > cursor.primaryKey) {
      cursor.continuePrimaryKey("javascript", lastPrimaryKey);
      return;
    }
    // update lastIteratedArticleId
    setLastIteratedArticleId(cursor.primaryKey);
    // preload 5 articles into the unread list;
    unreadList.push(cursor.value);
    if (++count < 5) {
      cursor.continue();
    }
};

Specifications

Specification	Status	Comment
Indexed Database API DraftThe definition of 'continuePrimaryKey()' in that specification.	Recommendation

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`continuePrimaryKey`	Chrome Full support 58	Edge Full support 79	Firefox Full support 51 Full support 51 No support 10 — 51 Prefixed' Prefixed' Implemented with the vendor prefix: moz	IE No support No	Opera Full support 45	Safari Full support 10.1	WebView Android Full support 58	Chrome Android Full support 58	Firefox Android Full support 51	Opera Android Full support 43	Safari iOS Full support 10.3	Samsung Internet Android Full support 7.0

Legend

Full support: Full support
No support: No support
Requires a vendor prefix or different name for use.': Requires a vendor prefix or different name for use.