Matthew Halliday wrote:
> I used the SQLite Studio to create the table so used the DATETIME data type
> for that, and although I used yyyy-mm-dd hh:mm:ss in the script
That is correct.
> it seems to have reverted it to dd/mm/yy hh:mm:ss.
That would not be usable.
Check the actual format with the sqlite3 command-line shell.
Assuming the timestamp format is usable, you can compute the differences
with a statement like this:
-- add three columns; then:
UPDATE MyTable
SET (diff_used, diff_free, diff_free_pc)
= (SELECT MyTable.used_mb - ifnull(prev.used_mb, 0),
MyTable.free_mb - ifnull(prev.free_mb, 0),
MyTable.free_pc - ifnull(prev.free_pc, 0)
FROM MyTable AS prev
WHERE prev.date_time < MyTable.date_time
ORDER BY date_time DESC
LIMIT 1);
This is much faster if there is an index on date_time.
Regards,
Clemens
_______________________________________________
sqlite-users mailing list
sqlite-users@mailinglists.sqlite.org
http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
