mysql - how can i use variable table $r1 in the query $r2 instead of table name on FROM clause in php file - 


$r1 = mysqli_query($con,"select course_id,status attendance stud_id = '$stud_id'");  $r2 = mysqli_query($con,"select course_name,status **$r1** natural join course stud_id = '$stud_id'");

you may have use subquery this.

$r2 = mysqli_query($con,"select course_name,status          (select course_id,status attendance stud_id = '$stud_id')          natural join course stud_id = '$stud_id'");

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