ON DUPLICATE KEY UPDATE
MySQL has something like this:
INSERT INTO visits (ip, hits)
VALUES ('127.0.0.1', 1)
ON DUPLICATE KEY UPDATE hits = hits + 1;
As far as I'm know this feature doesn't exist in SQLite, what I want to know is if there is any way to archive the same effect without having to execute two queries. Also, if this is not possible, what do you prefer:
INSERT OR IGNORE INTO visits VALUES ($ip, 0);
UPDATE visits SET hits = hits + 1 WHERE ip LIKE $ip;
This requires the "ip" column to have a UNIQUE (or PRIMARY KEY) constraint.
EDIT: Another great solution: https://stackoverflow.com/a/4330694/89771.
I'd prefer UPDATE (+ INSERT if UPDATE fails)
. Less code = fewer bugs.
The current answer will only work in sqlite OR mysql (depending on if you use OR or not). So, if you want cross dbms compatibility, the following will do...
REPLACE INTO `visits` (ip, value) VALUES ($ip, 0);
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