title: How to enforce a business rule across database tables?
body: <p>I am working on this BANK MANAGEMENT SYSTEM database project (oracle) on sql developer and I have made some progress but I am stuck at this minor problem</p>
  
  <p>The problem: I have a table of <code>employee</code> with <code>employee id</code> as primary key and in that table there is an attribute of <code>position</code> (clerk, manager etc), and <code>branch id</code> (the branch at which that employee works) which is a foreign key (referenced to <code>branch_id</code> of <code>branch</code> table). Then there is a table of <code>branch</code> with <code>branch id</code> as primary key and <code>manager_id</code> as foreign key (referenced to the <code>employee_id</code> of <code>employee</code> table).</p>
  
  <p>What kind of query should I write to ensure that the employee who is the manager of that branch also must have the term 'Manager" as his/her position.</p>