php mysql语法错误

Question

我正在与语法错误作斗争，但我无法真正找到问题所在。

这是我的问题

 $res2 = mysql_query("SELECT * FROM wp_postmeta PM1
                      WHERE PM1.meta_key = '_pronamic_google_maps_latitude'
                      AND PM1.post_id = '$id'
                      JOIN wp_postmenta PM2 
                      WHERE PM2.post_id = PM1.post_id 
                      AND PM2.meta_key = '_pronamic_google_maps_longitude'")
         or die(mysql_error());

出现这个错误:

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'JOIN wp_postmeta PM2' at line 3

有人可以给我提示我缺少什么吗？

Answer 1

首先必须进行连接，然后进行其余的查询。所以像

 $res2 = mysql_query("SELECT * FROM wp_postmeta PM1
                                  JOIN wp_postmenta PM2 on PM1.post_id = PM2.post_id
                                  WHERE PM1.meta_key = '_pronamic_google_maps_latitude'
                                  AND PM1.post_id = '$id'
                                  AND PM2.meta_key = '_pronamic_google_maps_longitude' 
                                   ") or die(mysql_error()) ;