title: Show the default value for a variable
body: <p>I am using <code>SET GLOBAL &lt;variable&gt; = &lt;value&gt;</code> to modify dynamic settings in mysql and I am wondering if there is some way to get the default value for each variable? For instance, if I use the following:</p>
  
  <pre><code>SET GLOBAL max_connections = 1000;
  </code></pre>
  
  <p>and then list the variable using:</p>
  
  <pre><code>SHOW GLOBAL VARIABLES LIKE 'max_connections';
  </code></pre>
  
  <p>I can see the modified value <code>1000</code>, but is there possible to get the default value for this system variable without checking the configuration files?</p>
  
  <p>I am using mysql 5.7 on ubuntu 16.04.</p>