【发布时间】：2019-09-12 13:58:49
【问题描述】：
我已经使用 laravel 大约 4 年了，但现在我面临着我最大的挑战。我正在重构和扩展一个旧的PHP 应用程序，用于映射我工作的办公室。我需要以某种方式将这个巨大的SQL 查询集成到 Laravel 的 QueryBuilder 中，以提供急切加载的关系。
流程是这样的
Building => hasMany: Floor => hasMany: Seat => hasMany: BookedSeat => belongsTo: User
其中Building、Floor、Seat 和BookedSeat 是Eloquent 模型。
我的巨大查询从BookedSeat 和Seat 中选择基于许多其他条件的当前日期预订，例如预订座位的人是否在家办公、度假等（这些存储在其他一些表）并在BookedSeat 实例上设置一个名为Status 的属性，以了解Seat 是否在当天被占用
现在我正在尝试将此原始查询集成到构建 JSON 层次结构中，然后将其发送到在前端运行的 Vue.js 应用程序。
层次结构类似于：
{
"buildings": [
{
// properties
"floors" : [
{
//properties
"seats": [
{
//properties
"booked": [
{
"user": "some user model",
"Status": "some booked status"
}
]
},
// other seats
]
},
// other floors
]
},
//other buildings
]
}
巨大的查询返回一个对象数组，然后我可以用它们来水合BookedSeat 集合，但我不知道如何使用这个集合或直接使用巨大的查询来急切加载@987654338 @ for each Seat for each Floor for each Building 让框架为我完成繁重的工作。
我尝试的是构建如下方法：
public static function bookedSeatsForFloor(Relation $seatQuery, Relation $bookedQuery, Carbon $forDate)
{
$format = $forDate->format('Y-m-d H:m:i');
$bindings = $seatQuery->getBindings();
/** @var AvailableSeatsQuerySimple $availableSeats */
$availableSeats = new AvailableSeatsQuerySimple($bindings, $format); // bindings are my floor id's and I'm feeding them to my big query in order to have control over which floors to load depending on the user's rights
return DB::raw($availableSeats->getRawQuery());
}
然后这样称呼它：
Floor::where('id', $someId)->with(['seats' => static function ($seatQuery) use ($_that) {
/**
* Add to each seat the manager and the active booking
*/
$seatQuery->with(['booked' => static function ($bookedQuery) use ($seatQuery, $_that) {
return self::bookedSeatsForFloor($seatQuery, $bookedQuery, $_that->forDate);
}, 'manager'])->orderBy('seat_cir');
}]);
但我需要使用$bookedQuery->select('something') 或$bookedQuery->setQuery('some query builder instance') 以某种方式修改bookedSeatsForFloor 方法中的$bookedQuery，但我不知道如何将巨大的查询转换为Builder 实例。
谢谢！
PS：由于复杂性，我最好跳过将庞大的查询重写为雄辩的语法
添加细节：
因此，根据要求，这是我的原始查询，我根据公司政策更改了一些数据库/表名称
SET NOCOUNT ON;
DECLARE
@the_date DATETIME;
SET @the_date = (SELECT CONVERT(DATETIME, ?, 120));
SELECT seat_identifier,
user_id,
FromDate,
ToDate,
Status
FROM (
SELECT d.seat_identifier,
d.user_id,
d.FromDate,
d.ToDate,
CASE
WHEN d.Status IS NULL
THEN 0
WHEN d.Status = 2
THEN 2
WHEN d.Status != 0
THEN CASE
WHEN -- New, OnGoing Request in Main_DB_Name
ho.status = 1 -- New StatusType in Main_DB_Name
OR
ho.status = 4 -- Pending StatusType in Main_DB_Name
OR
twl.status = 1 -- New StatusType in Main_DB_Name
OR
twl.status = 4 -- Pending StatusType in Main_DB_Name
OR
li.status = 1 -- New StatusType in Main_DB_Name
OR
li.status = 4 -- Pending StatusType in Main_DB_Name
OR
ctaf.status = 1 -- New StatusType2 in Main_DB_Name
OR
ctaf.status = 2 -- Ongoing StatusType2 in Main_DB_Name
THEN
2 --> Pending seat in MyApplication
WHEN -- Approved Request in Main_DB_Name
ho.status = 2
OR
twl.status = 2
OR
li.status = 1
OR
li.status = 2
OR
ctaf.status = 1
OR
ctaf.status = 2
THEN 0 -- Free Seat MyApplication
ELSE 1 -- Taken Seat MyApplication
END
END as 'Status'
FROM (
SELECT seats.seat_identifier as seat_identifier,
c.user_id,
c.FromDate,
c.ToDate,
c.Status
FROM (
SELECT fo_bs.seat_identifier,
fo_bs.user_id,
fo_bs.FromDate,
fo_bs.ToDate,
fo_bs.Status
FROM MyApplication.another_schema.BookedSeats fo_bs
INNER JOIN MyApplication.another_schema.seats AS seats ON fo_bs.seat_identifier = seats.seat_identifier
WHERE fo_bs.FromDate <= @the_date
AND fo_bs.ToDate >= @the_date
AND fo_bs.Status IN (1, 2)
AND seats.floor_id IN (###FLOOR_IDS###) -- will replace this from php with a list of "?,?,?" depending on how many floor_ids are in the query bindings
) c
INNER JOIN MyApplication.another_schema.seats AS seats ON c.seat_identifier = seats.seat_identifier) d
LEFT JOIN (SELECT requester, status
from Main_DB_Name.schema.HOME_OFFICE
WHERE Main_DB_Name.schema.HOME_OFFICE.from_date <= @the_date
and Main_DB_Name.schema.HOME_OFFICE.to_date >= @the_date) ho ON d.user_id = ho.requester
LEFT JOIN (SELECT requester, status
from Main_DB_Name.schema.TEMPORARY_WORK_LOCATION
WHERE Main_DB_Name.schema.TEMPORARY_WORK_LOCATION.from_date <= @the_date
and Main_DB_Name.schema.TEMPORARY_WORK_LOCATION.to_date >= @the_date) twl
ON d.user_id = twl.requester
LEFT JOIN (SELECT employee, status
from Main_DB_Name.schema.LEAVE_INVOIRE
WHERE Main_DB_Name.schema.LEAVE_INVOIRE.leave_date = @the_date) li ON d.user_id = li.employee
LEFT JOIN (SELECT requester, status
from Main_DB_Name.schema.TRAVEL
WHERE Main_DB_Name.schema.TRAVEL.from_date <= @the_date
and Main_DB_Name.schema.TRAVEL.until_date >= @the_date) ctaf
ON d.user_id = ctaf.requester
) y
我的模型/关系如下：
class Building extends Model {
/* Properties */
public function floors()
{
return $this->hasMany(Floor::class);
}
}
class Floor extends Model {
/* Properties */
public function building()
{
return $this->belongsTo(Building::class);
}
public function seats()
{
return $this->hasMany(Seat::class);
}
}
class Seat extends Model {
/* Properties */
public function floor()
{
return $this->belongsTo(Floor::class);
}
public function booked()
{
return $this->hasMany(BookedSeat::class);
}
}
class BookedSeat extends Model {
/* Properties */
public function user()
{
return $this->belongsTo(User::class);
}
public function seat()
{
return $this->belongsTo(Seat::class);
}
}
【问题讨论】：
-
像
Buildings::with('floors.seats.bookedseats.users')->get()这样的东西不会给你所有的东西吗？ （假设with部分是您关系的正确名称） -
是的，但它会为我提供数据库中的所有内容。我需要以某种方式使用这个复杂的查询，因为它有一系列基于许多约束的
CASE-WHEN(T-SQL) 并设置了 @ 987654353@ 为每个BookedSeat实例动态 -
然后我在前端使用该状态来允许用户预订座位或不预订
-
您能否提供一个包含尽可能少的模型/关系和实际原始查询的简单示例？
-
将原始查询集成到您的急切加载设置中非常复杂。我会建议一种不同的方法：分别执行主查询和原始查询，然后使用
Model::setRelation()手动将原始结果插入层次结构。你可以查看关系的match()方法来了解 Laravel 是如何处理这个问题的。
标签： php laravel eloquent eager-loading laravel-query-builder