APEX BFILE
Now I had to change the application to store the BLOB content in a file and set a pointer in a BFILE column leaving the BLOB column empty. Therefore I wrote a view converting BFILE to BLOB and some instead of triggers to convert BLOB to BFILE.
Then I rewrote my Apex pages using the view instead of the table. It doesn’t work. I noticed that when using the table Apex is first executing an INSERT leaving the BLOB empty and after that an UPDATE to fill the BLOB column when creating a new record. When using the view instead of the table the INSERT is executed but not the UPDATE.