内部加入选择的SQL查询

Question

我想编写如下的SQL查询。它的语法不正确。我该如何纠正它？

$sql_package_feature = "SELECT f.feature_id, f.feature_name FROM tbl_feature f 
LEFT JOIN SELECT * FROM tbl_feature_and_profile fp WHERE fp.profile_id= ?) ON 
f.feature_id = fp.feature_id AND f.package_id = fp.package_id WHERE fp.feature_id 
IS NULL AND f.package_id = ? ORDER BY f.feature_id"; 

Answer 1

我觉得在子选择之后缺少'作为fp'。试试这个查询：

SELECT 
     f.feature_id, 
     f.feature_name 
FROM tbl_feature f 
LEFT JOIN (SELECT * FROM tbl_feature_and_profile fp WHERE fp.profile_id= ?) 
    as fp ON (f.feature_id = fp.feature_id AND f.package_id = fp.package_id) 
WHERE 
    fp.feature_id IS NULL AND f.package_id = ? ORDER BY f.feature_id 

Answer 2

如果你加入一个子选择，你必须命名它。将名称放在子选择而不是表格里面：

SELECT f.feature_id, f.feature_name 
FROM tbl_feature f 
LEFT JOIN (
    SELECT * 
    FROM tbl_feature_and_profile 
    WHERE profile_id= ? 
) fp ON f.feature_id = fp.feature_id AND f.package_id = fp.package_id 
WHERE fp.feature_id IS NULL AND f.package_id = ? 
ORDER BY f.feature_id 

Answer 3

尝试一个没有嵌套SELECT语句的JOIN，只有一个表名。 尝试：

$sql_package_feature = 
"SELECT f.feature_id, f.feature_name 
FROM 
tbl_feature f 
LEFT JOIN 
tbl_feature_and_profile fb 
ON f.feature_id = fp.feature_id AND f.package_id = fp.package_id 
WHERE fp.feature_id IS NULL AND f.package_id = ? AND fp.profile_id = ? ORDER BY f.feature_id"; 

Answer 4

你没有第二表来给出一个名字，但你在接通后条款使用它。 fp在右括号后丢失：

SELECT f.feature_id, f.feature_name 
FROM tbl_feature f 
LEFT JOIN (
    SELECT * 
    FROM tbl_feature_and_profile fp 
    WHERE fp.profile_id= ? 
) fp 
ON  f.feature_id = fp.feature_id 
    AND f.package_id = fp.package_id 
WHERE fp.feature_id IS NULL 
    AND f.package_id = ? 
ORDER BY f.feature_id" 
;