PHP学习：laravel学习教程之关联模型

$user->posts()->where('active', 1)->get();

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class User extends Model
{
 /**
  * Get the phone record associated with the user.
  */
 public function phone()
 {
  return $this->hasOne('App\Phone');
 }
}

$phone = User::find(1)->phone;

return $this->hasOne('App\Phone', 'foreign_key');

return $this->hasOne('App\Phone', 'foreign_key', 'local_key');

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Phone extends Model
{
 /**
  * Get the user that owns the phone.
  */
 public function user()
 {
  return $this->belongsTo('App\User');
 }
}

/**
 * Get the user that owns the phone.
 */
public function user()
{
 return $this->belongsTo('App\User', 'foreign_key');
}

/**
 * Get the user that owns the phone.
 */
public function user()
{
 return $this->belongsTo('App\User', 'foreign_key', 'other_key');
}

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Post extends Model
{
 /**
  * Get the comments for the blog post.
  */
 public function comments()
 {
  return $this->hasMany('App\Comment');
 }
}

$comments = App\Post::find(1)->comments;
foreach ($comments as $comment) {
 //
}

$comments = App\Post::find(1)->comments()->where('title', 'foo')->first();

return $this->hasMany('App\Comment', 'foreign_key');
return $this->hasMany('App\Comment', 'foreign_key', 'local_key');

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Comment extends Model
{
 /**
  * Get the post that owns the comment.
  */
 public function post()
 {
  return $this->belongsTo('App\Post');
 }
}

$comment = App\Comment::find(1);
echo $comment->post->title;

/**
 * Get the post that owns the comment.
 */
public function post()
{
 return $this->belongsTo('App\Post', 'foreign_key');
}

/**
 * Get the post that owns the comment.
 */
public function post()
{
 return $this->belongsTo('App\Post', 'foreign_key', 'other_key');
}

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class User extends Model
{
 /**
  * The roles that belong to the user.
  */
 public function roles()
 {
  return $this->belongsToMany('App\Role');
 }
}

$user = App\User::find(1);
foreach ($user->roles as $role) {
 //
}

$roles = App\User::find(1)->roles()->orderBy('name')->get();

return $this->belongsToMany('App\Role', 'role_user');

return $this->belongsToMany('App\Role', 'role_user', 'user_id', 'role_id');

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Role extends Model
{
 /**
  * The users that belongs to the role.
  */
 public function users()
 {
  return $this->belongsToMany('App\User');
 }
}

$user = App\User::find(1);
foreach ($user->roles as $role) {
 echo $role->pivot->created_at;
}

return $this->belongsToMany('App\Role')->withPivot('column1', 'column2');

return $this->belongsToMany('App\Role')->withTimestamps();

return $this->belongsToMany('App\Role')->wherePivot('approved', 1);
return $this->belongsToMany('App\Role')->wherePivotIn('approved', [1, 2]);

countries
 id - integer
 name - string
users
 id - integer
 country_id - integer
 name - string
posts
 id - integer
 user_id - integer
 title - string

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Country extends Model
{
 /**
  * Get all of the posts for the country.
  */
 public function posts()
 {
  return $this->hasManyThrough('App\Post', 'App\User');
 }
}

class Country extends Model
{
 public function posts()
 {
  return $this->hasManyThrough(
   'App\Post', 'App\User',
   'country_id', 'user_id', 'id'
  );
 }
}

posts
 id - integer
 title - string
 body - text
comments
 id - integer
 post_id - integer
 body - text
likes
 id - integer
 likeable_id - integer
 likeable_type - string

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class like extends Model
{
 /**
  * Get all of the owning likeable models.
  */
 public function likeable()
 {
  return $this->morphTo();
 }
}
class Post extends Model
{
 /**
  * Get all of the post's likes.
  */
 public function likes()
 {
  return $this->morphMany('App\Like', 'likeable');
 }
}
class Comment extends Model
{
 /**
  * Get all of the comment's likes.
  */
 public function likes()
 {
  return $this->morphMany('App\Like', 'likeable');
 }
}

$post = App\Post::find(1);
foreach ($post->likes as $like) {
 //
}

$like = App\Like::find(1);
$likeable = $like->likeable;

use Illuminate\Database\Eloquent\Relations\Relation;
Relation::morphMap([
 App\Post::class,
 App\Comment::class,
]);

use Illuminate\Database\Eloquent\Relations\Relation;
Relation::morphMap([
 'posts' => App\Post::class,
 'likes' => App\Like::class,
]);

posts
 id - integer
 name - string
videos
 id - integer
 name - string
tags
 id - integer
 name - string
taggables
 tag_id - integer
 taggable_id - integer
 taggable_type - string

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Post extends Model
{
 /**
  * Get all of the tags for the post.
  */
 public function tags()
 {
  return $this->morphToMany('App\Tag', 'taggable');
 }
}

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Tag extends Model
{
 /**
  * Get all of the posts that are assigned this tag.
  */
 public function posts()
 {
  return $this->morphedByMany('App\Post', 'taggable');
 }
 /**
  * Get all of the videos that are assigned this tag.
  */
 public function videos()
 {
  return $this->morphedByMany('App\Video', 'taggable');
 }
}

$post = App\Post::find(1);
foreach ($post->tags as $tag) {
 //
}

$tab = App\Tag::find(1);
foreach ($tag->videos as $video) {
 //
}

<?ph
namespace App;
use Illuminate\Database\Eloquent\Model;
class User extends Model
{
 /**
  * Get all of the posts for the user.
  */
 public function posts()
 {
  return $this->hasMany('App\Post');
 }
}

$user = App\User::find(1);
$user->posts()->where('active', 1)->get();

$user = App\User::find(1);
foreach ($user->posts as $post) {
 //
}

// Retrieve all posts that have at least one comment...
$posts = App\Post::has('comments')->get();

// Retrieve all posts that have three or more comments...
$posts = Post::has('comments', '>=', 3)->get();

// Retrieve all posts that hava at least one comment with votes...
$posts = Post::has('comments.votes')->get();

// Retrieve all posts with at least one comment containing words like foo%
$posts = Post::whereHas('comments', function ($query) {
 $query->where('content', 'like', 'foo%'); 
})->get();

$posts = App\Post::withCount('comments')->get();
foreach ($posts as $post) {
 echo $post->comments_count;
}

$posts = Post::withCount(['votes', 'comments' => function ($query) {
 $query->where('content', 'like', 'foo%');
}])->get();
echo $posts[0]->votes_count;
echo $posts[0]->comments_count;

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Book extends Model
{
 /**
  * Get the author that wrote the book.
  */
 public function author()
 {
  return $this->belongsTo('App\Author');
 }
}

$books = App\Book::all();
foreach ($books as $book) {
 echo $book->author->name;
}

$books = App\Book::with('author')->get();
foreach ($books as $book) {
 echo $book->author->name;
}

select * from books
select * from authors where id in (1, 2, 3, 4, 5, ...)

$books = App\Book::with('author', 'publisher')->get();

$books = App\Book::with('author.contacts')->get();

$users = App\User::with(['posts' => function ($query) {
 $query->where('title', 'like', '%first%');
}])->get();

$users = App\User::with(['posts' => function ($query) {
 $query->orderBy('created_at', 'desc');
}])->get();

$books = App\Book::all();
if ($someCondition) {
 $books->load('author', 'publisher');
}

$books->load(['author' => function ($query) {
 $query->orderBy('published_date', 'asc');
}]);

$comment = new App\Comment(['message' => 'A new comment.']);
$post = App\Post::find(1);
$post->comments()->save($comment);

$post = App\Post::find(1);
$post->comments()->saveMany([
 new App\Comment(['message' => 'A new comment.']),
 new App\Comment(['message' => 'Another comment.']),
]);

App\User::find(1)->roles()->save($role, ['expires' => $expires]);

$post = App\Post::find(1);
$comment = $post->comments()->create([
 'message' => 'A new comment.',
]);

$account = App\Account::find(10);
$user->account()->associate($account);
$user->save();

$user->account()->dissociate();
$user->save();

$user = App\User::find(1);
$user->roles()->attach($roleId);

$user->roles()->attach($roleId, ['expires' => $expires]);

// Detach a single role from the user...
$user->roles()->detach($roleId);
// Detach all roles from the user...
$user->roles()->detach();

$user = App\User::find(1);
$user->roles()->detach([1, 2, 3]);
$user->roles()->attach([1 => ['expires' => $expires], 2, 3]);

$user = App\User::find(1);
$user->roles()->updateExistingPivot($roleId, $attributes);

$user->roles()->sync([1, 2, 3]);

$user->roles()->sync([1 => ['expires' => true], 2, 3]);

<?php
namespace App;
use Illuminate\Database\Eloquent\Model;
class Comment extends Model
{
 /**
  * All of the relationships to be touched.
  *
  * @var array
  */
 protected $touches = ['post'];
 /**
  * Get the post that the comment belongs to.
  */
 public function post()
 {
  return $this->belongsTo('App\Post');
 }
}

$comment = App\Comment::find(1);
$comment->text = 'Edit to this comment!';
$comment->save();