php - 计算数组中值的数量

Question

我目前正在尝试计算特定价格范围内的特性数量，而我正在运行的查询仅返回值 1。显然我做错了什么 - 不那么 MySQL 也无济于事/精通 PhP..有人介意帮忙吗？

查询如下:

    $apart = $wpdb->get_var("SELECT m1.post_id
    FROM hj_postmeta m1
    INNER JOIN hj_postmeta m2 ON m1.post_id = m2.post_id
    WHERE m1.meta_key = 'price'
    AND m1.meta_value
    BETWEEN 50000 AND 74999 AND m2.meta_key = 'property_type'
    AND m2.meta_value = 'apartment'");

$apartprice = count($apart); 

非常感谢。

Answer 1

使用get_results 作为get_var function returns a single variable from the database :

$apart = $wpdb->get_results("SELECT m1.post_id
    FROM hj_postmeta m1
    INNER JOIN hj_postmeta m2 ON m1.post_id = m2.post_id
    WHERE m1.meta_key = 'price'
    AND m1.meta_value
    BETWEEN 50000 AND 74999 AND m2.meta_key = 'property_type'
    AND m2.meta_value = 'apartment'");

$apartprice = count($apart); 

或使用 get_var 计算全部:

$apart = $wpdb->get_var("SELECT COUNT(m1.post_id)
    FROM hj_postmeta m1
    INNER JOIN hj_postmeta m2 ON m1.post_id = m2.post_id
    WHERE m1.meta_key = 'price'
    AND m1.meta_value
    BETWEEN 50000 AND 74999 AND m2.meta_key = 'property_type'
    AND m2.meta_value = 'apartment'");

$apartprice = $apart;