title: Practical difference between .pls and .sql file in oracle
body: <p>What is the practical difference between .pls and .sql file in oracle. 
  What are the restrictions on different types of statements in both?</p>
  
  <p>I am given a project in unix(korn script) which uses both .sql and .pls files in different places. Trying to figure out which should be used where.</p>