In message <[EMAIL PROTECTED]>, Bob <[EMAIL PROTECTED]> writes >Hi Pete, >I did sort one of my dbs by "year" when I was re-organizing, but luckily I'd >saved the sql dump. >Why I sorted it was because it was originally a flat file, which I'd converted. >It didn't have timestamps, just the dates.
I assume that you mean before you got the data into MySQL. As far as I know, you cannot SORT MySQL - to be pedantic, you cannot physically change the order of the records. You don't need to, you 'display' them in a different order using indexes. There may be some obscure way of sorting, but it would probably involve destroying the table, and rebuilding a copy of it, so wouldn't be done on a working table. > >As you can guess, I'm still learning to use mysql databases *grin*. >Thanks for the advice. > >Just got MAX() working after about 4hrs. I'd missed out the "AS logged" (It >was >nattering me. Don't need a haircut now!) You don't need it, but the field returned by SELECT UNIX_TIMESTAMP(MAX(logged)) FROM forum (with no 'as logged') will be called "UNIX-TIMESTAMP(MAX(logged))" and won't be easy to manipulate - hence the 'as logged' > >MAX(logged) to me, looks the more logical way of doing it. >Any idea which would be the most efficient? They are different: > >SELECT UNIX_TIMESTAMP(MAX(logged)) AS logged FROM forum This one gives you the date of the most recent record. >or >SELECT UNIX_TIMESTAMP(logged) AS logged FROM forum ORDER BY logged DESC LIMIT This one gives you the date of the n most recent records, in order from newest to oldest. You missed a number off after the LIMIT. If there is an index on logged, then to the best of my knowledge, method 2 will be faster. The database only has to read the last entry in the index. They are treated differently by SELECT. But no-one will see the difference - it will be half a squillisecond - or less. -- Pete Clark http://www.hotcosta.com http://www.spanishholidaybookings.com Community email addresses: Post message: [email protected] Subscribe: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] List owner: [EMAIL PROTECTED] Shortcut URL to this page: http://groups.yahoo.com/group/php-list Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/php-list/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
