title: Combine two tables in SQLite
body: <p>I have two tables, ta and tb:</p>
  
  <p>ta:</p>
  
  <pre><code>key col1  
  --------
  k1 a 
  k2 c 
  </code></pre>
  
  <p>tb:</p>
  
  <pre><code>key col2  
  -------
  k2 cc 
  k3 ee 
  </code></pre>
  
  <p>They connected by "key". I want to know how can I get a table, tc, like:</p>
  
  <pre><code>key col1 col2  
  -------------
  k1 a  
  k2 c cc 
  k3  ee
  </code></pre>
  
  <p>Is there a easy method instead of inserting every record? They are one million records of tables so I need an effective way. </p>