DpcTabular

The DpcTabular type describes the configuration of a database-oriented Persister that is operating in tabular mapping mode.

{
  mode: "tabular";
  tables?: {
    load?: DpcTabularLoad;
    save?: DpcTabularSave;
  };
  values?: DpcTabularValues;
  autoLoadIntervalSeconds?: number;
}

This configuration can only be used when the Persister is persisting a regular Store. For those database-oriented Persister types that support MergeableStore data, you will need to use JSON-serialization, es described in the DpcJson section.

It is important to note that both the tabular mapping in ('save') and out ('load') of an underlying database are disabled by default. This is to ensure that if you pass in an existing populated database you don't run the immediate risk of corrupting or losing all your data.

This configuration therefore takes a tables property object (with child load and save property objects) and a values property object. These indicate how you want to load and save Tables and Values respectively. At least one of these two properties are required for the Persister to do anything!

Note that if you are planning to both load from and save to a database, it is important to make sure that the load and save table mappings are symmetrical. For example, consider the following.

import type {DatabasePersisterConfig} from 'tinybase';

export const databasePersisterConfig: DatabasePersisterConfig = {
  mode: 'tabular',
  tables: {
    load: {petsInDb: 'pets', speciesInDb: 'species'},
    save: {pets: 'petsInDb', species: 'speciesInDb'},
  },
};

See the documentation for the DpcTabularLoad, DpcTabularSave, and DpcTabularValues types for more details on how to configure the tabular mapping mode.

Columns in SQLite database have no type, and so in this mode, the table can contain strings and numbers for Cells and Values, just as TinyBase does. Booleans, unfortunately, are stored as 0 or 1 in SQLite, and cannot be distinguished from numbers.

In PostgreSQL databases, all Cell and Value columns are expected to be typed as text, and the strings, booleans, and numbers are all JSON-encoded by the Persister.

The 'Dpc' prefix indicates that this type is used within the DatabasePersisterConfig type.

import type {DatabasePersisterConfig} from 'tinybase';

export const databasePersisterConfig: DatabasePersisterConfig = {
  mode: 'tabular',
  tables: {
    load: {petsInDb: 'pets', speciesInDb: 'species'},
    save: {pets: 'petsInDb', species: 'speciesInDb'},
  },
  values: {
    load: true,
    save: true,
    tableName: 'my_tinybase_values',
  },
};