src/sequelize/lib/dialects/abstract/connection-manager.js
/**
   * Drain the pool and close it permanently
   *
   * @returns {Promise}
   */
Drain the pool and close it permanently
@returns {Promise}
Drain the pool and close it permanently @returns { Promise }
async close() {
    this.getConnection = async function getConnection() {
      throw new Error('ConnectionManager.getConnection was called after the connection manager was closed!');
    };
    return await this._onProcessExit();
  }
async close ( ) { this . getConnection = async function getConnection ( ) { throw new Error ( 'ConnectionManager.getConnection was called after the connection manager was closed!' ) ; } ; return await this . _onProcessExit ( ) ; }
Drain the pool and close it permanently
 @returns {Promise}
Drain the pool and close it permanently @returns { Promise }
// Mark close of pool