


How to query the latest associated model of a model with specific conditions in Laravel?
I just asked a question on StackOverflow, please answer it.
http://stackoverflow.com/ques...
A Package model has many Step models. There are two fields in Step, the tinyint type status field and the timestamp field.
Suppose a Package A has the following steps
At 10 o'clock on the 18th, status is 1
At 9:00 on the 19th, status is 2
Suppose a Package B has the following steps
At 8:00 on the 19th, status is 1
At 9:00 on the 19th, status is 2
At 10 o'clock on the 19th, status is 3
In this way, the latest step status of A is 2, and the latest step status of B is 3.
Then, how to query the packages whose latest step status is 2?
I tried adding
to the package model<code>public function steps() { return $this->hasMany('App\Step'); } public function status() { return $this->steps()->latest()->limit(1); } </code>
Then query like this
<code>Package::whereHas('status', function ($q) { $q->where('status', 2); })->get(); </code>
But I can’t get the expected results.
The so-called not expected result means that if there is only B in the packages table, I want to query the packages whose latest step status is 2, and the latest step status of B is 3, so the result should be empty, but the result of querying like this is not It is not empty, but contains B.
Then I tried to change to
<code>public function status() { return $this->hasOne('App\Step')->latest(); } </code>
It’s still the same.
I just learned Laravel, and I was very confused when I encountered this problem. I also searched a lot of Google, but I couldn’t find the answer I wanted. I hope you can help me, thank you!
Using Laravel 5.3
Reply content:
I just asked a question on StackOverflow, please answer it.
http://stackoverflow.com/ques...
A Package model has many Step models. There are two fields in Step, the tinyint type status field and the timestamp field.
Suppose a Package A has the following steps
At 10 o'clock on the 18th, status is 1
At 9:00 on the 19th, status is 2
Suppose a Package B has the following steps
At 8:00 on the 19th, status is 1
At 9:00 on the 19th, status is 2
At 10 o'clock on the 19th, status is 3
In this way, the latest step status of A is 2, and the latest step status of B is 3.
Then, how to query the packages whose latest step status is 2?
I tried adding
to the package model<code>public function steps() { return $this->hasMany('App\Step'); } public function status() { return $this->steps()->latest()->limit(1); } </code>
Then query like this
<code>Package::whereHas('status', function ($q) { $q->where('status', 2); })->get(); </code>
But I can’t get the expected results.
The so-called not expected result means that if there is only B in the packages table, I want to query the packages whose latest step status is 2, and the latest step status of B is 3, so the result should be empty, but the result of querying like this is not It is not empty, but contains B.
Then I tried to change to
<code>public function status() { return $this->hasOne('App\Step')->latest(); } </code>
It’s still the same.
I just learned Laravel, and I was very confused when I encountered this problem. I also searched a lot of Google, but I couldn’t find the answer I wanted. I hope you can help me, thank you!
Using Laravel 5.3
<code>Package::whereHas('steps', function ($q) { $q->where('status', 2); })->get();</code>

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