title: Replace an unknown string within a line using Bash
body: <p>I want to be able to modify <code>db001</code> with a string I pass into the command via CLI. At any given time <code>db001</code> could be a different value so I can't just look for that value.</p>
  
  <pre><code>./myscript modify_db &lt;new value&gt;
  </code></pre>
  
  <h1>myfile.txt</h1>
  
  <pre><code>./myscript modify_db mynewdbname002
  Before: database_node=db001.mydomain.local
  After: database_node=mynewdbname002.mydomain.local    
  
  ./myscript modify_db db003
  Before: database_node=mynewdbname002.mydomain.local
  After: database_node=db003.mydomain.local    
  </code></pre>