PHP + Mysql：来自第一个查询的动态表名，用于执行第二个查询

I have three tables, the first is a table storing applications, the second is a table storing different online forms (different types of applications), the third is a table that stores actual form data:

    TABLE applications=========
    -applicationID (PK)
    -formID (FK)
    -formRecordID
    ====================  

    TABLE forms=========
    -formID (PK)
    -formName
    -tableName (could be 'form_businessLicense','eventLicense',etc)
    ====================

    TABLE form_businessLicense=====
    -recordID (PK)
    -dateSubmitted
    -(a whole bunch of other data)
    ===============================

"formRecordID" points to "recordID" in "form_businessLicense" or "eventLicense". Since it could reference any table, it can't be a foreign key. So instead I grab the tableName from the "forms" table, then build a query to get all the application data from, say "form_businessLicense".

So I need to get data from, say, all applications plus a bit of data from the application form filled out (ex:form_businessLicense). I'm just going to paste my code (I'm actually querying all applications in a given set of IDs):

$applications = $this->selectAll(
            "SELECT applicationID, formName, tableName, fieldIdentifier, formRecordID, dateSubmitted, DATE_FORMAT(dateSubmitted,'%c/%e/%Y') AS dateSubmittedFormat
            FROM applications AS a 
            JOIN forms AS f
            ON a.formID = f.formID
            WHERE a.applicationID IN (".$applicationIDs.")
            ORDER BY dateSubmitted ASC"
        );

        for($a=0;$a<count($applications);$a++){
            $form = $this->select("SELECT ".$applications[$a]['fieldIdentifier']." AS identifierName
                FROM ".$applications[$a]['tableName']."
                WHERE recordID = ".$applications[$a]['formRecordID']
            );
            $applications[$a]['identifierName'] = $form['identifierName'];
        }

Is there any way to merge these two queries into one so I don't have to loop over all results and run a separate query for each result? I feel like I could maybe do this with a JOIN but I'm not sure how to reference the "tableName" and "formRecordID" for use in the same SQL statement.

You need to apply join to three tables, and select count(PK) of third table while adding a group by clause for the PK of third table.

Note: PK used for Primary Key