Php 我可以在内部联接子句之前包含where子句吗

我有这个密码

$q = $conn->query("SELECT facultydetails.F_NAME,Paper_title from faculty inner join facultydetails on faculty.Fac_ID = facultydetails.Fac_ID where (paper_path = 'NULL' OR paper_path = '') and  (certificate_path = 'NULL' OR certificate_path = '') and (report_path = 'NULL' OR report_path = '') " );

现在我需要添加一个条件，其中用户将提供id，并且只有与id相关的内容应该被选中，我才能使用此代码

$q = $conn->query("SELECT facultydetails.F_NAME,Paper_title from faculty where facultydetails.Fac_ID='$FacID' inner join facultydetails on faculty.Fac_ID = facultydetails.Fac_ID where (paper_path = 'NULL' OR paper_path = '') and  (certificate_path = 'NULL' OR certificate_path = '') and (report_path = 'NULL' OR report_path = '') " ); 

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使用php时，不能在内部联接之前添加where子句

SELECT facultydetails.F_NAME,Paper_title 
from faculty 
inner join facultydetails on faculty.Fac_ID = facultydetails.Fac_ID 
where facultydetails.Fac_ID='$FacID' 
AND (paper_path = 'NULL' OR paper_path = '') and  (certificate_path = 'NULL' OR certificate_path = '') and (report_path = 'NULL' OR report_path = '')

内部联接的语法如下所示：

SELECT column_list
FROM t1
INNER JOIN t2 ON join_condition1
INNER JOIN t3 ON join_condition2
...
WHERE where_conditions;

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不能在内部联接之前添加where，但可以将条件添加到on子句中，如：

"SELECT facultydetails.F_NAME,Paper_title ".
"from faculty ".
"inner join facultydetails ".
"on (facultydetails.Fac_ID='$FacID') and (faculty.Fac_ID = facultydetails.Fac_ID) ".
"where (paper_path = 'NULL' OR paper_path = '') and  (certificate_path = 'NULL' OR certificate_path = '') and (report_path = 'NULL' OR report_path = '') "

或者，您可以对教员表进行预筛选，如：

"SELECT facultydetails.F_NAME,Paper_title ".
"from (select * from faculty where (facultydetails.Fac_ID='$FacID')) f ".
"inner join facultydetails ".
"on f.Fac_ID = facultydetails.Fac_ID ".
"where (paper_path = 'NULL' OR paper_path = '') and  (certificate_path = 'NULL' OR certificate_path = '') and (report_path = 'NULL' OR report_path = '') "

编辑：

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在SQL中，如果代码为“上方”或“下方”，则单个查询中的某些其他部分将不能保证在它之前执行。

一个SQL只能有一个where子句，您可以如上所述使用它。我希望这对您有用。