In some database systems, it can be beneficial to use "NOT NULL" as much as possible when defining tables. It usually allows for a slightly tighter storage encoding, and also allows some optimizations to occur.
AFAICT, in sqlite it only seems important for constraining the data appropriately. For a column which does not contain null data, it looks like the storage doesn't change between when it's defined with NOT NULL or without (I'm guessing this is basically because of manifest typing). Also, the EXPLAIN output doesn't change at all when I add or remove the NOT NULL. So it would seem that the actual performance would never change, nor would the storage footprint, so long as you don't ever attempt to insert null data (in which case the NOT NULL version would convert it to an appropriate default value, which might cause changes to storage or performance). Anyone got holes to shoot in my reasoning? Thanks, scott [It's sort of hard to search for emails to sqlite-users about "NOT NULL". There are many references to "NOT NULL" in table examples people include with their questions :-).] ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
