datasource config

        'lookup' => [
            'className' => 'Cake\Database\Connection',
            'driver' => 'Cake\Database\Driver\Mysql',
            'persistent' => 'false,',
            'host' => 'localhost',
            'username' => 'root',
            'password' => '',
            'database' => 'lookup',
            'encoding' => 'utf8',
            'cacheMetadata' => false,
            'quoteIdentifiers' => true,
        ],
        'test_lookup' => [
            'className' => 'Cake\Database\Connection',
            'driver' => 'Cake\Database\Driver\Mysql',
            'persistent' => 'false,',
            'host' => 'localhost',
            'username' => 'root',
            'password' => '',
            'database' => 'test_lookup',
            'encoding' => 'utf8',
            'cacheMetadata' => false,
            'quoteIdentifiers' => true,
        ],

TimeSheetsFixture.php

<?php
namespace App\Test\Fixture;

use Cake\TestSuite\Fixture\TestFixture;

/**
 * TimeSheetsFixture
 *
 */
class TimeSheetsFixture extends TestFixture
{
    public $connection = 'test_lookup';

    /**
     * Fields
     *
     * @var array
     */
    // @codingStandardsIgnoreStart
    public $fields = [
        'id' => ['type' => 'integer', 'length' => 10, 'unsigned' => true, 'null' => false, 'default' => null, 'comment' => '', 'autoIncrement' => true, 'precision' => null],
        'start_time' => ['type' => 'datetime', 'length' => null, 'null' => false, 'default' => null, 'comment' => '', 'precision' => null],
        'end_time' => ['type' => 'datetime', 'length' => null, 'null' => false, 'default' => null, 'comment' => '', 'precision' => null],
        'rate' => ['type' => 'integer', 'length' => 10, 'unsigned' => true, 'null' => false, 'default' => null, 'comment' => '', 'precision' => null, 'autoIncrement' => null],
        'notes' => ['type' => 'text', 'length' => null, 'null' => true, 'default' => null, 'comment' => '', 'precision' => null],
        '_constraints' => [
            'primary' => ['type' => 'primary', 'columns' => ['id'], 'length' => []],
        ],
        '_options' => [
            'engine' => 'InnoDB',
            'collation' => 'utf8_general_ci'
        ],
    ];
    // @codingStandardsIgnoreEnd

    /**
     * Records
     *
     * @var array
     */
    public $records = [
        [
            'id' => 1,
            'start_time' => '2015-09-30 01:50:10',
            'end_time' => '2015-09-30 01:50:10',
            'rate' => 1,
            'notes' => 'Lorem ipsum dolor sit amet, aliquet feugiat. Convallis morbi fringilla gravida, phasellus feugiat dapibus velit nunc, pulvinar eget sollicitudin venenatis cum nullam, vivamus ut a sed, mollitia lectus. Nulla vestibulum massa neque ut et, id hendrerit sit, feugiat in taciti enim proin nibh, tempor dignissim, rhoncus duis vestibulum nunc mattis convallis.'
        ],
    ];
}

TimeSheetsTable.php

<?php
namespace App\Model\Table;

use Cake\ORM\Query;
use Cake\ORM\Table;
use Cake\Database\Schema\Table as Schema;
use Cake\ORM\RulesChecker;
use Cake\Validation\Validator;

/**
 * TimeSheets Model
 */
class TimeSheetsTable extends Table
{

    /**
     * Initialize method
     *
     * @param array $config The configuration for the Table.
     * @return void
     */
    public function initialize(array $config)
    {
        $this->table('time_sheets');
        $this->primaryKey('id');
    }

    public static function defaultConnectionName()
    {
        return 'lookup';
    }
}