我认为现在我明白了您要做什么.当您使用WP_Query运行自定义查询并将限制设置为每页仅获得5个帖子时,该查询将仅检索5个帖子,而该查询仅包含5个帖子, BUT 为了便于分页,WP_Query仍然遍历整个数据库,并计算与查询条件匹配的所有帖子.

当您查看查询的$found_posts和$max_num_pages属性时,可以看到这一点.让我们举个例子:

您有20个帖子属于默认帖子类型post.您只需即可获得最新的5条帖子,无需分页.您的查询看起来像这样

 $q = new WP_Query( 'posts_per_page=5' );
 

• var_dump( $q->posts )将为您提供最新的5条帖子
• echo $q->found_posts将为您提供20
• echo $q->max_num_pages将为您提供4

在只有几篇文章的网站上,这项额外工作的影响微乎其微,但是如果您正在运行一个拥有数百或数千篇文章的网站,这可能会非常昂贵.如果您只需要5个最新职位,这会浪费资源

有一个未记录的参数,称为no_found_rows,该参数使用布尔值,可以在找到所需的5个帖子后使用它来使您的查询保释.这将强制WP_Query在检索到查询的帖子数量后不再寻找符合条件的帖子.此参数已经内置在get_posts中,这就是为什么get_posts比WP_Query快一点的原因,尽管get_posts使用WP_Query

结论

最后,如果您不打算对查询使用分页,明智的做法是在查询中 'no_found_rows=true' 以节省浪费的资源.

I think that now I understand what you are trying to do. When you run a custom query with WP_Query and set the limit to get only 5 posts per page, only 5 posts will be retrieved by the query and that query will only hold 5 posts, BUT for the sake of pagination, WP_Query still runs through the whole database and counts all the posts that matches the criteria of the query.

That can be seen when you look at the $found_posts and $max_num_pages properties of the query. Lets take an example:

You have 20 posts belonging to the default post type post. You only need the latest 5 posts without pagination. Your query looks like this

$q = new WP_Query( 'posts_per_page=5' );

• var_dump( $q->posts ) will give you the latest 5 posts as expected
• echo $q->found_posts will give you 20
• echo $q->max_num_pages will give you 4

The impact of this extra work is minimal on sites with only a few posts, but this can gt expensive if you are running a site with hundreds or thousands of posts. This is a waste of resources if you are only ever going to need the 5 latest posts

There is an undocumented parameter called no_found_rows which uses boolean values which you can use to make your query bail after it found the 5 posts you need. This will force WP_Query not to look for any more posts mathing the criteria after it has retrieved the amount of posts queried. This parameter is already build into get_posts, that is why get_posts is a bit faster than WP_Query although get_posts uses WP_Query

Conclusion

In conclusion, if you are not going to use pagination on a query, it is always wise to 'no_found_rows=true' in your query to speed things up and to save on wasting resources.

与@Pieter Goosen讨论了问题的评论之后,我认为我可以回答问题并解释我的错误.

关键是found_posts让我感到困惑.我认为,该数字是检索到的帖子,但不是.这是符合条件的帖子数.就像WP_Query有两部分一样:一部分用于查找(所有)帖子,另一部分用于在检查pagination参数时获取内容.因此,我们有一个$post_count属性,它是获取的帖子数(Codex说The number of posts being displayed),当然等于posts_per_page参数,以及$posts数组属性上的项目数.

所以WP_Query并没有做任何无用的工作,正如我认为的^^

希望这对其他人有帮助！

After the conversation with @Pieter Goosen on the comments of the question, I think I can answer the question and explain my mistake.

The key is that found_posts was confussing me. I thougth that, that number is the posts retrieved but is not. It is the number of posts that match the criteria. It's like the WP_Query had 2 parts: one for finding (all) the posts, and other for fetching the content, when it checks for the pagination parameters. So we have the $post_count property that is the number of posts fetched (Codex says The number of posts being displayed), that of course is equal to the number on posts_per_page parameter, and the number of items on the $posts array property.

So WP_Query is not doing any useless work, as I thought ^^

Hope this helps others!

好,让您拥有名为"blog_posts"的帖子类型,并且您希望获取5个该帖子类型的帖子.这是您需要做的

 $args = array(
        'post_type' => 'blog_posts',
        'posts_per_page' => '5',
);


$query = new WP_Query($args);
 

上面的查询将返回5个类型为'blog_posts'的帖子,如果它不是自定义帖子类型,则只需替换'post_type' => 'posts',,如果您想获取所有帖子,请像这样'posts_per_page' => '-1',,以获取更多详细信息 WP查询

Ok , lets you have post type called 'blog_posts' , and you want to fetch 5 posts of that post type . Here is what you need to do

$args = array(
        'post_type' => 'blog_posts',
        'posts_per_page' => '5',
);


$query = new WP_Query($args);

The above query will return 5 posts of type 'blog_posts' , if it is not a custom post type , then just replace like this 'post_type' => 'posts', if you want to fetch all posts then replace like this 'posts_per_page' => '-1', , for more details WP Query

我知道@ user1750063已经提到了代码,但是请尝试

 $args = array (
    'post_type'              => 'custom_post',
    'nopaging'               => false,
    'posts_per_page'         => '5',
    'order'                  => 'DESC',
    'orderby'                => 'ID',
);

$query = new WP_Query( $args );

if ( $query->have_posts() ) {
    while ( $query->have_posts() ) {
        $query->the_post();
        // display content
    }
} else {
    // display when no posts found
}

wp_reset_postdata();     // Restore original Post Data
 

I know that @user1750063 has mentioned the code but try this

$args = array (
    'post_type'              => 'custom_post',
    'nopaging'               => false,
    'posts_per_page'         => '5',
    'order'                  => 'DESC',
    'orderby'                => 'ID',
);

$query = new WP_Query( $args );

if ( $query->have_posts() ) {
    while ( $query->have_posts() ) {
        $query->the_post();
        // display content
    }
} else {
    // display when no posts found
}

wp_reset_postdata();     // Restore original Post Data

我将使用自定义字段进行限制,请在下面查看此查询示例:

 $wp_query = new WP_Query("orderby=DESC&post_type=portfolio&meta_key=FeaturedProject&meta_value=1&posts_per_page=6");
 

它将返回6个特色项目.

I would limit it with custom fields, check this query sample below:

$wp_query = new WP_Query("orderby=DESC&post_type=portfolio&meta_key=FeaturedProject&meta_value=1&posts_per_page=6");

It will return 6 Featured projects.