SQL

Typetta provides comprehensive support for major SQL databases, including PostgreSQL, CockroachDB, MSSQL, MySQL, MariaDB, SQLite3, Better-SQLite3, Oracle, and Amazon Redshift. Such extensive support is ensured by the fact that, internally, the KnexJS library is used. KnexJS is an open.source query-builder that is widely used in Node JS and is supported by a large community. With a test coverage greater than 90%, it is also commonly considered a software suitable for use in a corporate setting.

All the features of Typetta allow direct access to a KnexJS instance, ensuring great flexibility and a wide range of features with which to directly access the database.

How to connect

In line with official documentation, connecting to an SQL database using KnexJS can be implemented as follows:

import knex from 'knex'

async function run() {
  const knexInstance = knex({
    client: 'mysql',
    connection: {
      host : '127.0.0.1',
      port : 3306,
      user : 'your_database_user',
      password : 'your_database_password',
      database : 'myapp_test'
    }
  });
}
run().catch(console.dir);

Note that it is the knex instance that handles connection pooling, so each JS Node process must generally use a single KnexJS instance, configuring it specifically:

import knex from 'knex'

async function run() {
  const knexInstance = knex({
    client: 'mysql',
    connection: {
      host : '127.0.0.1',
      port : 3306,
      user : 'your_database_user',
      password : 'your_database_password',
      database : 'myapp_test'
    },
    pool: { min: 0, max: 7 }
  });
}
run().catch(console.dir);

Creation of the EntityManager

Unlike connection, the EntityManager can be instantiated multiple times and with different parameters. For example, it is advisable to create an EntityManager for each calling context (for example, each REST or GraphQL call).

The EntityManager requests an input reference to the KnexJS instance that it will use to access the various data model entities. Here is an example configuration:

const entityManager = new EntityManager({
  knex: {
    default: knexInstace,
  },
})

And finally a complete example:

import knex from 'knex'

async function run() {
  const knexInstance = knex({
    client: 'mysql',
    connection: {
      host : '127.0.0.1',
      port : 3306,
      user : 'your_database_user',
      password : 'your_database_password',
      database : 'myapp_test'
    },
    pool: { min: 0, max: 7 }
  });

  const entityManager = new EntityManager({
    knex: {
      default: knexInstance,
    },
  })

  // ...
  // const users = entityManager.user.findAll();
  // ...
}
run().catch(console.dir);