Question

我知道$ downloadfile - 我想要$ user_id。经过反复试验，我发现这就是我想要的。但它是3个单独的查询和3个while循环。我觉得有更好的方法。是的，我对我正在做的事情只有一点点了解。）

$result = pod_query("SELECT ID FROM wp_posts WHERE guid LIKE '%/$downloadfile'");
while ($row = mysql_fetch_assoc($result)) { 
    $attachment = $row['ID']; }

$result = pod_query("SELECT pod_id FROM wp_pods_rel WHERE tbl_row_id = '$attachment'");
while ($row = mysql_fetch_assoc($result)) {
    $pod_id = $row['pod_id']; }

$result = pod_query("SELECT tbl_row_id FROM wp_pods_rel WHERE tbl_row_id = '$pod_id' AND field_id = '28'");
while ($row = mysql_fetch_assoc($result)) {
    $user_id = $row['tbl_row_id']; }

Answer 1

假设我正确理解您的查询，这应该有效：

SELECT wp.ID, wpr.pod_id, wpr.tbl_row_id
FROM wp_pods_rel AS wpr
JOIN wp_posts AS wp
  ON wp.ID = wpr.tbl_row_id
WHERE wpr.field_id = '28'
  AND wp.guid LIKE '%/$downloadfile'

Answer 2

SELECT wp_posts.ID, wp_pods_rel.pod_id, wp_pods_rel.tbl_row_id
FROM wp_posts
JOIN wp_pods_rel ON wp_posts.ID = wp_pods_rel.tbl_row_id
WHERE wp_posts.guid LIKE '%/$downloadfile' AND wp_pods_rel.field_id = '28'

是否可以结合这3个mySQL查询？

2 个答案: