title: Postgresql create view
body: <p>I have the following columns in Table A which records users fingerprint "transaction" every time they check in or check out from a building.</p>
  
  <pre><code>CREATE TABLE user_transactions(
      id serial PRIMARY KEY,
      staff_id INT4,
      transaction_time TIMESTAMP,
      transaction_type INT4
  );
  </code></pre>
  
  <p>In a single day a user can have many transactions. How can I create a view that with the following stucture?</p>
  
  <pre><code>    staff_id INT4
      transaction_date DATE
      first_transaction TIMESTAMP --first finger scan of the day
      last_transaction TIMESTAMP  --last finger scan of the day
      number_of_transaction INT4  --how many times did the user scan for the day
  </code></pre>