As far as I can tell,
the un-value NULL is not described anywhere in the doc
as being something that can be assigned to a column.
E.g. :
. not listed as a constant (well that's reasonable as it isn't)
. not listed as an expression (is NULL an expression?)
. not explicitly listed under the INSERT and UPDATE commands
as a valid syntactic unit as an alternative to an expression
(If it is not an expression)
I do see it listed as a valid keyword but there is no description there.
To put it another way, the following syntax is apparently not permitted :
UPDATE my_nullable_table SET nullable_col = NULL;
(I am not referring to other null-related constructs such as IS NULL, IFNULL etc)
I have to assume I'm missing something?
Or is it that NULL is so, well, null, that it cannot be described?
John
