title: Add an Order column to an existing table that contains data with SQL query
body: <p>Recently I was working on a project that needs to add a column to sort existing records. To clarify the subject, I will give a small example. Suppose we have a table to store the names of Corona vaccine injection centers and another table to register the people who come to each of these centers. After collecting the data, we come to the conclusion that to manage the order of turns, we must add a &quot;Order&quot; column to Person table. How can I do this by writing a query without losing the data collected so far?</p>
  <p>Here is the table of centers:</p>
  <p><a href="https://i.stack.imgur.com/SqJ0i.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SqJ0i.jpg" alt="enter image description here" /></a></p>
  <p>And this is the table of person:</p>
  <p><a href="https://i.stack.imgur.com/kwqJK.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/kwqJK.jpg" alt="enter image description here" /></a></p>
  <p>And what I expect is something like this:</p>
  <p><a href="https://i.stack.imgur.com/QoUzl.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QoUzl.jpg" alt="enter image description here" /></a></p>
  <p>PS: I use SQL to create tables and store data.</p>