Oracle returns zero rows when using distinc clause or order by clause

Hi guys,

i've got weird problemy with one of our 11.2.0.1 database ( I know it should be patched but it's not up to me).

The problem is, when selecting data without distinct clause everything works fine. But if I use distinct clause in my SELECT statement from some views (not every view) it shows no rows.

For example:

Select distinct A from MYview; ---> no rows

Select A from MYview; ---> many records

Also - i saw that the problem is also connected with order by clause.

For example:

Select A from MYview order by 1; ----> no rows

Select A from MYview; ---> shows all data