InStr and Length Problem Ora-01460

I wonder if anybody can help. I have a where clause which looks for a string pattern e.g.

Select * from Table where Instr(String1,string2) > 0

When String1 is less than 4000 characters the query works, when this is increased to 6000 characters, I get the error message "ORA-01460: unimplemented or unreasonable conversion requested". I have checked the reference data and it says that a string up 32767 charcaters can be handled in Pl/SQL.

Can somebody please explain why this is happening and how I can resolve it ?

Thanks in Advance. Received on Mon Nov 14 2005 - 17:22:19 CST