我有一个带有字段的自定义帖子类型Exercise 和Tempo. 下面是一个可能的示例：

练习1-100
练习2-104
练习3-96
练习1-104
练习2-110
练习3-100

如何使用WP\\u Query仅返回最高Tempo 各的Exercise?

期望的结果是：

练习1-104练习2-110练习3-100

编辑：

我终于按照Rarst的建议让它工作了（见下文）。谢谢你的帮助！

 function opl_user_practice_sheet_test($atts, $content = null){

if ( is_user_logged_in()) {
global $current_user;
wp_get_current_user();
echo \'User: \' . $current_user->user_login . "\\n";

global $post;

$atts = shortcode_atts( array(
\'title\'           => \'User Practice Sheet\',
\'count\'           => -1
), $atts);

// query arguments
$args = array(
\'post_type\'       => \'opl_exercise\',
\'post_status\'     => \'publish\',
\'orderby\'         => \'created\',
\'order\'           => \'DESC\',
\'posts_per_page\'  => $atts[\'count\']
);

// fetch practice sheet tempos
$practice_sheet_exercises = new WP_Query($args);

// check if tempos come back
if($practice_sheet_exercises->have_posts()){

// init output
$output = \'\';

// build output
$output .= \'<div class="user-practice-sheet">
              <table>
                <thead>
                  <tr>
                    <td>Exercise</td>
                    <td>Submitted Tempo</td>
                    <td>Next Target Tempo</td>
                  </tr>
                </thead>
                <tbody>\';

while($practice_sheet_exercises->have_posts()){

  $practice_sheet_exercises->the_post();

  $exercise_type = get_post_meta($post->ID, \'opl_exercise_type\', true);
  $exercise_number = get_post_meta($post->ID, \'opl_exercise_number\', true);


  $tempo_query = new WP_Query(
    array(
      \'post_type\'       => \'opl_tempo_submission\',
      \'order_by\'        => \'meta_value_num\',
      \'meta_key\'        => \'opl_submission_tempo\',
      \'order\'           => \'DESC\',
      \'posts_per_page\'  => 1,
      \'meta_query\'      => array(
        \'relation\' => \'AND\',
        array(
          \'key\' => \'opl_submission_exercise_type\',
          \'value\' => $exercise_type,
          \'compare\' => \'=\'
        ),
        array(
          \'key\' => \'opl_submission_exercise_number\',
          \'value\' => $exercise_number,
          \'compare\' => \'=\'
        )
      )
    )
  );

  if ( $tempo_query->have_posts() ) {
      while ( $tempo_query->have_posts() ) {

        $tempo_query->the_post();

        $submission_tempo = get_post_meta($post->ID, \'opl_submission_tempo\', true);

  $output .= \'<tr>\';

  $output .= \'<td>\'.$exercise_type .\' \'. $exercise_number.\'</td>\';
  $output .= \'<td>\'.$submission_tempo.\'</td>\';
  $output .= \'<td></td>\';

  $output .= \'</tr>\';

     }

  }


}

$output .= \'</tbody>
            </table>
            </div>\';

// reset post data
wp_reset_postdata();

return $output;

} else {
return \'<p>No Practice Sheet Found</p>\';
}

}
}