title: what will be the sql query for checking same pairs of column values in a table?
body: <p>I have a table emp(id , name, salary) and having no primary key (i know that is a bad idea but my work is on inconsistent table)<br>
  I want a query to retrieve tuples which have same pairs of values (id, name)
  i tried using self join but not getting exact statement.
  Here same pair is considering but i am working for more than 2 attributes for comparison. plz help
  Example </p>
  
  <pre><code>     id     name   salary
       1      a       100
       1      b       100
       2      a       200
  
       1      a       300
       2      c       200
  </code></pre>
  
  <p>So i want to find tuple with same value of id and name. here it is(1,a)</p>