Drupal Blocks - Error Causes Display Problems
I just about destroyed my Drupal-powered allergy website today. I made one small change to the HTML in a block, and the whole website came up blank. With a blank website, I did not have admin access to the menu that changes the blocks!
Rather than panicking, I reasoned that I had made a fundamental typo in the HTML in the block I had just changed, and that must be in the database somewhere.
Using phpMyAdmin from the account back-end, I looked through various likely tables. The most obviously named, “blocks” was not the right table. It lists all blocks, along with their display status, display location etc.
Boxes is the correct table. It contains the content and title of all blocks that simply contain HTML.
Sure enough, I’d failed to close a quote in the HTML in the block I had just edited. Other things to look for: unmatched tags (especially the <DIV> tag, and unmatched angle brackets. I fixed it in phpMyAdmin and now the allergy website works again.