LEFT JOIN和WHERE導致錯誤

Question

我有一個嵌套的mysql_query。

$resultSub = mysql_query("SELECT * 
          FROM ensembles 
          WHERE en_name = $name 
         LEFT JOIN ensemble_names on ensembles.en_name = ensemble_names.en_nm_ID 
         LEFT JOIN students on ensembles.en_stu = students.s_ID 
         LEFT JOIN part_names on ensembles.en_part = part_names.p_nm_ID 
         ORDER BY $sort $orderBy"); 

查詢作品，未經WHERE子句，我認爲對於LEFT JOIN命令可以被過濾掉行罰款，但事實並非如此。

Answer 1

WHERE子句應放在左後加入：

$resultSub = mysql_query("SELECT * 
          FROM ensembles 
         LEFT JOIN ensemble_names on ensembles.en_name = ensemble_names.en_nm_ID 
         LEFT JOIN students on ensembles.en_stu = students.s_ID 
         LEFT JOIN part_names on ensembles.en_part = part_names.p_nm_ID 
          WHERE en_name = $name 
         ORDER BY $sort $orderBy"); 

Answer 2

好了，你把WHERE條款在錯誤的地方。

閱讀the documentation。