save attendance in database about zklibrary

[erkutcin]

i am trying to save attendance in database but i get this error can someone help me ?

Hi Aminechouchene98, i made all updates. But i am still not able to retrieve the datas. Could you advise me how did you do it? Thanks in advance

[IncubuzzCC]

Hi erkutcin ,
This likely seems to be a database issue on your end, and not a device issue with the library.

In my case the uid returns the position the user record is stored in the device while id is the actual user id.
In your case it looks like yours is storing a consecutive id in the uid field and the user id in the id field.
Therefore thw data structure may slightly vary across devices.

As long as you do not clear attendance records the device by using the clearAttendance() function, the device will give you the same data plus the new attendance records.
If you clear the attendance records, which you probably should every once in a while to keep the download from becoming slow,

We worked around this by creating a combined primary key (or you could use a unique index) over the user id and the date time field.

CREATE TABLE ``deviceusers` (
  `id` smallint(5) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(75) COLLATE utf8mb4_unicode_ci NOT NULL,
  `synctime` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  `fetched` tinyint(1) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`)
);

CREATE TABLE `deviceregs` (
  `deviceuser_id` smallint(5) unsigned NOT NULL,
  `time` datetime NOT NULL,
  `fetched` tinyint(3) unsigned NOT NULL DEFAULT '0',
  PRIMARY KEY (`deviceuser_id`,`time`),
  CONSTRAINT `deviceregs_deviceuser_id_foreign` FOREIGN KEY (`deviceuser_id`) REFERENCES `deviceusers` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
);

This way you could use INSERT IGNORE or capture inserts that fail due to duplication.

I hope this helps.

Sample device attendance:

[23] => Array([0] => 29, [1] => 3, [2] => 0, [3] => 2022-12-09 19:02:00)
[24] => Array([0] => 9, [1] => 9, [2] => 0, [3] => 2022-12-10 07:39:07)
[25] => Array([0] => 163, [1] => 162, [2] => 0, [3] => 2022-12-10 07:41:35)

Sample device users:

[9] => Array([0] => 9, [1] => Josef, [2] => 0, [3] => )
[29] => Array([0] => 3, [1] => Fred, [2] => 14, [3] => 696910)
[163] => Array([0] => 162, [1] => Bernard, [2] => 0, [3] => )