<?php namespace app\model; use DateTimeInterface; use support\Model; class Device extends Model { protected $table = 'device'; protected $primaryKey = 'device_id'; protected $keyType = 'string'; protected $dateFormat = 'U'; const CREATED_AT = 'device_addtimes'; const UPDATED_AT = null; public function serializeDate(DateTimeInterface $date) { return $date->format('Y-m-d H:i:s'); } public function ledger() { return $this->hasOne(DeviceLedger::class, 'device_ledger_id', 'join_device_ledger_id') ->select('device_ledger_id', 'device_ledger_name'); } }