I need to show/hide html content depending on whether a field value exists or not.
Previously I used your Advanced Conditional Region with DW server behaviors to achieve this.

How would I do this with the Database Connector?

Or would I have to code each block that I need to show/hide like so:

<?php if (isset({{product}})) { ?>
  <p>Product:<br />
    <?php echo {{product}}; ?></p>
  <?php }  ?>

Hello David,
just use the data-show/data-hide options in the data bindings panel.
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Thanks - I see now
Enclose the content one wants to show/hide in a DIV then div.data.show on the field.

Yes:
1. Select the binding, you want to check if exists or not, in the data bindings query tree (data bindings panel)
2. Select the tag you want to hide/show (make sure to select the tag in the properties inspector, for more precise selection)
3. Apply data.show or data.hide depending on if you want to show or hide the element if the binding has a value.