Selectors are not executed more than once until a related source cache is cleaned.
let books = await booksWithAuthors.read();
// Value will be returned from cache:
console.log(await booksWithAuthors.read());
console.log(await booksWithAuthors.read());
// Clean authors cache:
booksCollection.clean();
// Now books are fetched again, and parser function is executed. Authors still remain cached.
books = await booksWithAuthors.read();Cache can be cleaned manually using the "clean" method:
booksWithAuthors.clean();
await booksWithAuthors.read(); // Selector will be executed again