`Indexes`

An Indexes object lets you look up all the Row objects in a Table that have a certain Cell value.

This is useful for creating filtered views of a Table, or simple search functionality.

Create an Indexes object easily with the createIndexes function. From there, you can add new Index definitions (with the setIndexDefinition method), query their contents (with the getSliceIds method and getSliceRowIds method), and add listeners for when they change (with the addSliceIdsListener method and addSliceRowIdsListener method).

This module defaults to indexing Row objects by one of their Cell values. However, far more complex indexes can be configured with a custom function.

Example

This example shows a very simple lifecycle of an Indexes object: from creation, to adding a definition, getting its contents, and then registering and removing a listener for it.

import {createIndexes, createStore} from 'tinybase';

const store = createStore().setTable('pets', {
  fido: {species: 'dog'},
  felix: {species: 'cat'},
  cujo: {species: 'dog'},
});

const indexes = createIndexes(store);
indexes.setIndexDefinition(
  'bySpecies', // indexId
  'pets', //      tableId to index
  'species', //   cellId to index
);

console.log(indexes.getSliceIds('bySpecies'));
// -> ['dog', 'cat']
console.log(indexes.getSliceRowIds('bySpecies', 'dog'));
// -> ['fido', 'cujo']

const listenerId = indexes.addSliceIdsListener('bySpecies', () => {
  console.log(indexes.getSliceIds('bySpecies'));
});
store.setRow('pets', 'lowly', {species: 'worm'});
// -> ['dog', 'cat', 'worm']

indexes.delListener(listenerId);
indexes.destroy();

`Indexes`

Example

See also

Since

Getter methods

Listener methods

Configuration methods

Iterator methods

Lifecycle methods

Development methods