RE: [PHP-DB] Selecting next ID and less?
| From: | John W. Holmes | Date: | Tue, 22 Apr 2003 23:55:54 +0000 |
| Subject: | RE: [PHP-DB] Selecting next ID and less? | ||
| References: | 1 | Groups: | php.db |
| Request: | Send a blank email to php-db+get-27287@lists.php.net to get a copy of this message | ||
> I'm working on a puzzle game, where users must solve many different
> puzzles. Once they complete a puzzle, they will be able to try the
next
> puzzle. Each puzzle is stored as a row in the puzzle in a database
> table. The problem is, how would I select the puzzles the next
highest
> puzzle and lower? I could use a query something like "select * from
> puzzles where id <= $completedid + 1", but it would break is there
were
> any holes in the ID. Also, it would use the ID as something more than
a
> unique identifier for each row, which is a bad thing. Any suggestions
> for a better way?
Assuming you're the puzzle_id you're currently solving is $puzzle
Next Puzzle:
SELECT * FROM table WHERE puzzle_id > $puzzle ORDER BY puzzle_id ASC
LIMIT 1
Previous Puzzle:
SELECT * FROM table WHERE puzzle_id < $puzzle ORDER BY puzzle_id DESC
LIMIT 1
If no row is returned it means you're at the upper/lower limit.
---John W. Holmes...
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