Subject alter column type to blob sub_type text
Author Luca Lafranchi
Hi :)

As I shortly noticed, it is not possible to change a "varchar" column to
"blob sub_type text", because as the error message says domain changes
that involve blobs are not possible. I'm using Fb 1.0.2, and before
testing with Fb 1.5 I'd like to ask if such domain changes will be
allowed in future versions...