title: How do I write an IF statement with multiple conditions on the same line in Bash?
body: <p>I'm writing a script right now in Bash that will execute two SQL queries and analyze that queried data. One of the command line inputs takes in an environment variable, which can be one of three values. If it's not one of those values, the script displays a message that prompts the user to enter in a correct value. However, the script doesn't properly check the value, instead prompting the user. Here is my code:</p>
  
  <pre><code>if [[ -z $ENV1 || $ENV1 != "ITF" || $ENV1 != "Prod" || $ENV1 != "QA" ]]
  then
      read -rp "Please enter the first environment (ITF, Prod, QA): " ENV1
  fi
  echo $ENV1
  </code></pre>
  
  <p>I think it's a problem with having multiple ||'s in the if line. How can I go about checking for all for of those conditions?</p>