Php SQL数据库对齐语法错误(?) - Php SQL Syntax error by a database alignment (?)!

Php SQL Syntax error by a database alignment (?)!

抱歉，如果我只是瞎了眼，但这确实没有意义，因为我总是这样写，我看不出有什么问题。此外，我使用了多个SQL解决方案位仍然错误的语法…

我的php代码:

$sql1 = " SELECT table1.file_name, table2.path
                FROM table1 AS t1
                LEFT JOIN table2 AS t2
                ON t1.file_name = t2.path
                WHERE t2.path IS NULL OR t1.file_name <> t2.file_name OR t1.file_name <> t2.path";
    $sql2 = "INSERT INTO table3 (file_name) VALUES(".$sql1.")";
    Shopware()->Db()->query($sql2);

我的错误信息:

SQLSTATE[42000]: Syntax error or access violation: 1064 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 'SELECT table1.file_name, table2.path FROM (the first 2 letters of table1)' at line 1 in Zend'Db'Statement'Pdo.php on line 234

INSERT..SELECT语句写成:

INSERT INTO ... SELECT ... FROM ...;

Not as INSERT INTO ... VALUES (SELECT ... FROM ...);