At 08:59 AM 26/07/2011, you wrote:

>I am using FB 2.5 and I have a Blob type 2 field and I am trying to
>update it with a string value. I am getting an error that "filter not
>found to convert type 1 to type 2". How can I create that filter or
>pre-define the data to update the blob?

Do you mean sub_type 2? If so, it's not available for updating by users - it is a system BLOB (can't say which one without checking docs...there are lots of blobs in the metadata, all sub_types 2 and higher).

If you want to use sub_types for specific purposes, define them as a sub_type of less than zero. Blob filters are a special category of external function that you can write (in a language that can export dynamic libs with CDECL calling convention, like a UDF) to have the contents of one sub_type converted to another sub_type. You declare them in the database, similarly to the way you declare UDFs.

Better you describe what you are trying to do here...

./hb