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useRowCount

The useRowCount primitive returns the count of the Row objects in a given Table, and registers a listener so that any changes to that result will cause an update.

useRowCount(
  tableId: MaybeAccessor<string>,
  storeOrStoreId?: MaybeAccessor<undefined | StoreOrStoreId>,
): Accessor<number>
TypeDescription
tableIdMaybeAccessor<string>

The Id of the Table in the Store.

storeOrStoreId?MaybeAccessor<undefined | StoreOrStoreId>

The Store to be accessed: omit for the default context Store, provide an Id for a named context Store, or provide an explicit reference.

returnsAccessor<number>

The number of Row objects in the Table.

A Provider component is used to wrap part of an application in a context, and it can contain a default Store or a set of Store objects named by Id. The useRowCount primitive lets you indicate which Store to get data for: omit the optional final parameter for the default context Store, provide an Id for a named context Store, or provide a Store explicitly by reference.

When first rendered, this primitive will create a listener so that changes to the count of Row objects will cause an update. When the component containing this primitive is unmounted, the listener will be automatically removed.

Example

This example creates the TinyBase objects needed by the Solid primitive or component and calls it from within a reactive root.

import {createRoot} from 'solid-js';
import {
  createCheckpoints,
  createIndexes,
  createMetrics,
  createQueries,
  createRelationships,
  createStore,
} from 'tinybase';
import {useRowCount} from 'tinybase/ui-solid';

createRoot((dispose) => {
  const store = createStore()
    .setTables({
      pets: {
        fido: {species: 'dog', color: 'brown', next: 'felix'},
        felix: {species: 'cat', color: 'black'},
      },
      species: {dog: {price: 5}, cat: {price: 4}},
    })
    .setValues({open: true});
  const metrics = createMetrics(store).setMetricDefinition(
    'highestPrice',
    'species',
    'max',
    'price',
  );
  const indexes = createIndexes(store).setIndexDefinition(
    'bySpecies',
    'pets',
    'species',
  );
  const relationships = createRelationships(store)
    .setRelationshipDefinition('petSpecies', 'pets', 'species', 'species')
    .setRelationshipDefinition('nextPet', 'pets', 'pets', 'next');
  const queries = createQueries(store).setQueryDefinition(
    'petColors',
    'pets',
    ({select, where, param}) => {
      select('color');
      where((getCell) => getCell('species') == param('species'));
    },
    {species: 'dog'},
  );
  const checkpoints = createCheckpoints(store);
  store.setCell('pets', 'fido', 'color', 'walnut');
  checkpoints.setCheckpoint('updated color');
  metrics.getMetric('highestPrice');
  indexes.getSliceIds('bySpecies');
  relationships.getRemoteRowId('petSpecies', 'fido');
  queries.getResultRowIds('petColors');
  useRowCount('pets', store);
  dispose();
});

Since

v8.3.0