Can I add "NOT NULL" to PRISTINE table columns?

[Julian Foad]

In r1040574 I noted that the 'size' and 'md5_checksum' columns in the
PRISTINE table are never currently null.  The latter is required by
current code to be non-null.

I feel it would be better to have the schema specify 'NOT NULL' for
these two columns.  Just a feeling of Goodness, no concrete reasons.

I imagine it should be possible to add 'NOT NULL' to these columns
without performing a format bump or writing any upgrade code.  Am I
right?


 CREATE TABLE PRISTINE (
[...] 
      NULL if unknown, and (thus) the pristine copy is incomplete/unusable.
+     ### We always set this; there may be no need to allow NULL. Shall we
+         add "NOT NULL" to the schema? */
   size  INTEGER,
 
[...]
+     ### We always set this and require it to be non-null. Can we add
+         "NOT NULL" to the schema? */
   md5_checksum  TEXT
   );

- Julian