yesodweb/persistent — comment on commit 81fcd5818f98c5d33a3e98e3da18cd634bbdb6b1
File: persistent/Database/Persist/GenericSql/Internal.hs line 198
By meteficha:

While I didn't test it, I guess "FilterAnd []" will give similar problems, but you'd have to use "1=0" instead of "1=1".