title: How to insert values from a select query
body: <p>how do I insert the std_id value and sub_id value in the student_subject table</p>
  <pre><code>insert into student_subjects(student_id,subject_id)
              values(std_id,(select id from subjects 
                             where guid in 
                             (select * from 
                             unnest(string_to_array(subjects_colls,',')::uuid[])))::int);
  </code></pre>
  <pre><code>ERROR:  more than one row returned by a subquery used as an expression
  </code></pre>