How do I back out of adding an instance of a broken block?

Question:

I added a block instance through the block admin funtion but the block
was broken and all I could get displayed was the exception page.  

I tried deleting the corresponding row in the xar_block_instances table,
and now I can at least get back to a usable display, but when I view
block instances I see an "empty" instance that cannot be deleted.

Help!!!!


Answer:

(Go to the source, Luke;)

You must also delete the row in the xar_block_group_instances table with
xar_instance_id corresponding to the xar_id in the xar_block_instances
table (which, of course, you've already deleted).