The following was copied from the manual "Using the generated code -> Adapter/SelfServicing -> Filtering and Sorting -> The predicate system":
Using a FieldLikePredicate, you can perform case insensitive compares however, if the database is case sensitive, by setting the CaseSensitiveCollation property to true prior to passing the predicate to a fetch method like FetchEntityCollection(). This will perform the UPPERCASE variant of the field with the pattern specified.Please note that if you've set CaseSensitiveCollaction to true, you've to specify your pattern in uppercase as well.