title: SQL copy data from another table of database with specified column format on destination
body: <p>in current column of our table we save data in <code>JSON</code> format such as :</p>
  <pre class="lang-json prettyprint-override"><code>{
    &quot;ru&quot;:&quot;text&quot;,
    &quot;en&quot;:&quot;text&quot;
  }
  </code></pre>
  <p>and into another column of table we have a simple string as <code>varchar</code> without any format. here we want to copy all data from destination column into another database column as source with specifying format as <code>JSON</code>, it means we want to format <code>varchar</code> to <code>JSON</code> on copying data</p>
  <pre><code>          {
  &quot;text&quot;  =&gt;  &quot;ru&quot;:&quot;text&quot;,
              &quot;en&quot;:&quot;text&quot;
            }
  </code></pre>
  <p>this simple <code>SQL</code> command can copy data only but it doesn't have any solution to convert string to json data in destination table:</p>
  <pre class="lang-sql prettyprint-override"><code>INSERT INTO source_table.column 
  SELECT column FROM destination_table
  </code></pre>
  <p>how can i convert during copy data into column of destination table?</p>