SqlWeb is an extension of JsStore which allows to use sql query for performing database operation in IndexedDB.
https://github.com/ujjwalguptaofficial/sqlweb/wiki
var connection = new JsStore.Instance('jsstore worker path');
connection.runSql("select * from Customers").then(function(result) {
console.log(result);
});
For a complete example - check out below link.