MySQL SELECT、LEFT JOIN和COUNT(）在一个查询中返回错误

我遇到了相当简单的查询！

简单地说，我已经创建了一个搜索（过滤器）面板，现在我正在添加分页

我在返回当前查询中的行数时遇到问题，这主要取决于动态更改的$detailed_search_query变量。

我需要进行以下操作，并将COUNT（）正确添加到其中，这样新行总数将包含unique_id的总数。

当前SQL：

$sql = $db->prepare( "
              SELECT
                individuals.individual_id,
                individuals.unique_id,
                individuals.fullname,
                individuals.day_of_birth,
                TIMESTAMPDIFF(YEAR,individuals.day_of_birth,CURDATE()) AS age,
                individuals.gender,
                individuals.record_timestamp,
                individuals.active,
                individuals.deleted,
                individuals_dynamics.weight,
                individuals_dynamics.degree,
                individuals_dynamics.trainer_name
              FROM
                individuals as individuals
              LEFT JOIN
                individuals_dynamics AS individuals_dynamics ON individuals.unique_id = individuals_dynamics.individual_id
              WHERE
                $detailed_search_query $display recognized = 'yes' 
              GROUP BY
                individuals.record_timestamp
              ORDER BY $by $how
              LIMIT " . $limit);

如果我将COUNT（）添加到它，则PDO错误为Fatal error: Call to a member function execute() on a non-object。

这就是我的新查询（刚刚开始，其余的都一样）的样子，它返回上面的错误：

$sql = $db->prepare( "
                  SELECT
                    COUNT(individuals.unique_id),
                    individuals.individual_id,
                    individuals.unique_id,
                    individuals.fullname,
                    individuals.day_of_birth,

我在这里错过了什么？

第1版：

我如何使用COUNT（）的例子导致了简单的预查询：

 $sql              = $db->prepare("SELECT count(unique_id) FROM individuals");
 $sql->execute();
 $total            = $sql->fetchColumn();
 $pagination       = new Pagination($paginate_number);
 $limit            = $pagination->getLimit($total);

第2版：

是的，对，当我添加别名时，会返回相同的错误，例如：

$sql = $db->prepare( "
                  SELECT
                    COUNT(individuals.unique_id) as total,
                    individuals.individual_id,

第3版：

我对上一次EDIT很不满意，如果你添加别名，比如total，那么查询可以工作，但它只计算当前行并返回1，但我需要总行计数，例如：

Array
(
    [0] => Array
        (
            [total] => 1
            [0] => 1
            [individual_id] => 51
            [1] => 51
            [unique_id] => f598edae
            [2] => f598edae

第4版：

当PHP变量被替换时，我在WHERE子句中有这样的内容：

                  WHERE
                    individuals.fullname LIKE '%adam%' AND individuals_dynamics.degree BETWEEN '1' AND '3' AND EXTRACT(YEAR FROM (FROM_DAYS(DATEDIFF(NOW(),individuals.day_of_birth))))+0 BETWEEN '7' AND '10' AND individuals_dynamics.weight BETWEEN  '20' AND '40' AND individuals_dynamics.degree BETWEEN '7' AND '10' AND deleted != 'yes' AND active != 'no' AND recognized = 'yes' 
                  GROUP BY
                    individuals.record_timestamp

第5版：

所需的结果是在最终数组中具有密钥总数，该总数表示当前查询中基于动态PHP变量提取的结果总数，如$detailed_search_query和$display:

现在我总有1个。何时应为75:

Array
(
    [0] => Array
        (
            [total] => 1
            [0] => 1
            [individual_id] => 71
            [1] => 71
            [unique_id] => f598e2ae
            [2] => f598e2ae
            [fullname] => Name2 Name2 Name2
        )
    [1] => Array
        (
            [total] => 1
            [0] => 1
            [individual_id] => 65
            [1] => 65
            [unique_id] => b76497ca
            [2] => b76497ca
        )