如何通过分类术语从自定义WordPress MySQL查询中排除结果

Question

我只想展示那些没有分类"产品品牌"的"品牌slu"一词的帖子.

我当前的查询不适用过滤器:

SELECT DISTINCT * FROM $wpdb->posts AS p
  LEFT JOIN $wpdb->postmeta AS meta ON p.ID = meta.post_id
  LEFT JOIN $wpdb->term_relationships AS rel ON rel.object_id = p.ID
  LEFT JOIN $wpdb->term_taxonomy AS tax ON tax.term_taxonomy_id = rel.term_taxonomy_id
  LEFT JOIN $wpdb->terms AS term ON tax.term_id = term.term_id
WHERE 1=1
    AND p.post_type = 'product' 
    AND p.post_status = 'publish' 
    AND p.post_title LIKE '%$trimmed%' OR (meta.meta_key = 'product_model' AND meta.meta_value LIKE '%$trimmed%') 
    AND (tax.taxonomy = 'product-brand' AND term.slug NOT IN ('$protected'))

分类法或slug条件似乎都不适用于上述查询.

任何帮助表示赞赏!

Answer 1

笔记:

看起来你没有使用$wpdb->prepare(),所以你冒着SQL注入的风险.

我还认为你错过了相关OR部分的括号,所以你最终不会显示草稿.

替代方案:

我们应该能够使用WP_Query该类,而不是编写硬编码的SQL查询,并通过钩子/过滤器进行一些修改.

这是一个例子(PHP 5.4+):

$args = [ 
    '_meta_or_like_title' => $trimmed,        // Our new custom argument!
    'post_type'           => 'product',
    'post_status'         => 'publish',
    'meta_query'          => [
        [
            'key'     => 'product_model',
            'value'   => $trimmed,            // Your meta value
            'compare' => 'LIKE'
        ]
    ],
    'tax_query'    => [
        [
            'taxonomy'  => 'product-brand',
            'field'     => 'slug',
            'terms'     => $protected,        // Your terms array
            'operator'  => 'NOT IN'
        ]
    ]
];

_meta_or_like_title我在这里为另一个问题写的稍微修改过的插件支持自定义参数.

插入:

<?php
/**
 *  Plugin Name:   Meta OR LIKE Title query in WP_Query
 *  Description:   Activated through the '_meta_or_like_title' argument of WP_Query 
 *  Plugin URI:    http://stackoverflow.com/a/31241416/2078474
 *  Plugin Author: Birgir Erlendsson (birgire)
 *  Version:       0.0.1
 */

add_action( 'pre_get_posts', function( $q )
{
    if( $title = $q->get( '_meta_or_like_title' ) )
    {
        add_filter( 'get_meta_sql', function( $sql ) use ( $title )
        {
            global $wpdb;

            // Only run once:
            static $nr = 0; 
            if( 0 != $nr++ ) return $sql;

            // Modify WHERE part:
            $sql['where'] = sprintf(
                " AND ( %s OR %s ) ",
                $wpdb->prepare( 
                    "{$wpdb->posts}.post_title LIKE '%%%s%%'", 
                     $wpdb->esc_like( $title ) 
                ),
                mb_substr( $sql['where'], 5, mb_strlen( $sql['where'] ) )
            );
            return $sql;
        });
    }
}, PHP_INT_MAX );