php - MySQL subquery from another database where table name depends on main query -

hi trying sub query table(name: table_guest_id) database id table name depends on main query. here set of databases:

• three tables: events, profile, table_guest_id
• two databases: main , guest(dbname below make clear)
• main contains: events , profile
• guest contain: table_guest_id(where id = e.id)

and sql code:

    public function getlistattendee($user)     {         $sql = "select p.name e.user, e.id, e.date                  events e, profile p                 p.user_id=e.user , e.event_date >= curdate()                  , (select count(*)                       dbname.table_guest_[??note: need insert e.id??]                       a.event_id=e.id , a.user_id='{$user}' ,                      a.status='invited') > 0";      } 

i have put note id or e.id inserted, not working yet. please let me know if have different solution on how sub query table name of table depends on main query values. idea possible?

it seems trying perform variable substitution on sql table name.

  dbname.table_guest_[??note: need insert e.id??]  

you can't that™ directly in sql. you'll need write php code generate table name, or use string-processing feature mysql team calls prepared statements.

if different databases hosted on same mysql server, can write queries refer more 1 of them @ time. give database name table name. example, if have databases db1 , db2 can this.

 select whatever    db1.events e    join db2.user_118 u on whatever = whatever