title: TYPO3: How do i change a part of a string in the database with QueryBuilder?
body: <p>I am using TYPO3 10 and i would like to change a specific text/word inside the <strong>pi_flexform</strong> column in the <strong>tt_content</strong> table.</p>
  <p>The concept: I want to migrate the forms folder from <strong>user_upload</strong> to <strong>form_definitions</strong> (Updating a Project from TYPO3 8 to 10) using the QueryBuilder.</p>
  <p>I could just override the form_definitions folder back to the user_upload, but i want a clean structure. Now if i change the folder from where the forms are coming, the forms do not work anymore because in the database and in the <strong>pi_flexform</strong> column exists the following:</p>
  <pre><code>...
  &lt;field index=&quot;settings.persistenceIdentifier&quot;&gt;
        &lt;value index=&quot;vDEF&quot;&gt;1:/user_upload/NameOfTheForm.form.yaml&lt;/value&gt;
  &lt;/field&gt;
  ...
  </code></pre>
  <p>What i want, is to change the <code>1:/user_upload/</code> to <code>1:/form_definitions/</code>.</p>
  <p>I know i will have to use the UPDATE &amp; SET with QueryBuilder but i do not know how to use it for a specific string inside a string.</p>
  <p>How do i achieve this?</p>