The data filter in the Data Grid in version 11.6.1 is not work correctly
For example I have one table with one column that have the values: N,S,NULL if you apply the filter Column like 'N' in version 11.6.1 you have only 44 lines returned. If you apply the same filter in the version 11.5 you have 50 lines (50 lines is the correct count with value N)
WORKAROUND
Use Toad for Oracle 11.5
STATUS
Waiting for a fix in a future release of Toad for Oracle