# Knex database adapter > This is the last active development release of this package as **Keystone 5** is now in a 6 to 12 month active maintenance phase. For more information please read our [Keystone 5 and beyond](https://github.com/keystonejs/keystone-5/issues/21) post. [](https://changelogs.xyz/@open-keystone/adapter-knex) The [Knex](https://knexjs.org/#changelog) adapter is a general purpose adapter which can be used to connect to a range of different database backends. At present, the only fully tested backend is `Postgres`, however Knex gives the potential for `MSSQL`, `MySQL`, `MariaDB`, `SQLite3`, `Oracle`, and `Amazon Redshift` to be supported. ## Usage ```javascript const { KnexAdapter } = require('@open-keystone/adapter-knex'); const keystone = new Keystone({ adapter: new KnexAdapter({...}), }); ``` ## Config ### `schemaName` _**Default:**_ `'public'` All postgres tables are grouped within a schema and `public` is the default schema. ### `dropDatabase` _**Default:**_ `false` Allow the adapter to drop the entire database and recreate the tables / foreign keys based on the list schema in your application. This option is ignored in production, i.e. when the environment variable NODE_ENV === 'production'. ### `knexOptions` These options are passed directly through to Knex. See the [knex docs](https://knexjs.org/#Installation-client) for more details. _**Default:**_ ```javascript { client: 'postgres', connection: process.env.CONNECT_TO || process.env.DATABASE_URL || process.env.KNEX_URI } ``` ## Debugging To log all Knex queries, run the server with the environment variable `DEBUG=knex:query`. ## Setup Before running Keystone with the Knex adapter you should configure a database. By default Knex will look for a Postgres database on the default port, matching the project name, as the current user. In most cases this database will not exist and you will want to configure a user and database for your application. Assuming you're on MacOS and have Postgres installed the `build-test-db.sh` does this for you: ```shell ./build-test-db.sh ``` Otherwise, you can run these steps manually: ```shell allowCopy=false showLanguage=false createdb -U postgres keystone psql keystone -U postgres -c "CREATE USER keystone5 PASSWORD 'change_me_plz'" psql keystone -U postgres -c "GRANT ALL ON DATABASE keystone TO keystone5;" ``` If using the above, you will want to set a connection string of: `postgres://keystone5:change_me_plz@localhost:5432/keystone`