tstamp may not be updated after sorting changed because of cut/copy operation

[ReneLuecking]

Affected version(s)

All versions

Description

First of all I'm not sure if this is really considered a bug or working as intended.

I'm using tl_content as an example but in general all tables with pid and sorting are affected.

When moving content elements from one place to another Contao may update the sorting value of surrounding elements which where not explicitly moved. As an example lets say we have an article with 5 content elements in it:

id	sorting	tstamp	type
1	64	1000000000	headline
2	128	1000000000	text
3	129	1000000000	html
4	130	1000000000	image
5	131	1000000000	text

Now I want to move the elements with ID 4 and 5 between 2 and 3. To do this I select ID 4 and 5, click "Cut" and then "Paste after" ID 2. This results in the following data:

id	sorting	tstamp	type
1	64	1000000000	headline
2	128	1000000000	text
3	134	1000000000	html
4	129	1234567890	image
5	130	1234567890	text

ID 4 and 5 have updated sorting values to represent their new position and updated tstamps as I explicitly moved them. ID 3 also has an updated sorting value as it had to move down to make place for ID 4 and 5., BUT ID 3 does NOT have an updated tstamp as it was not moved explicitly.

Depending on the definition you could either say that ID 3 should have a new tstamp, as it has technically changed, but you could also say it should not have a new tstamp as it was not changed by a user.

The reason I even bring this topic up is the following: we have custom code in place to keep two Contao systems in sync. That means if something changes in system 1 it should also get updated in system 2. The tstamp is used to detect and sync any changes, otherwise we would always need to check all database entries for changes, as usually the tstamp gets updated if something changes. Except in this specific case.

I'm really not sure if that is an issue for anyone except me and if it should be changed or not. If it will be changed, as far as I know the following 3 statements in DC_Table would need to also update the tstamp:

contao/core-bundle/contao/drivers/DC_Table.php

Lines 1389 to 1392 in 28c3779

	$db
	->prepare("UPDATE " . $this->strTable . " SET sorting=? WHERE id=?")
	->limit(1)
	->execute($count++ * 128, $objNewSorting->id);

contao/core-bundle/contao/drivers/DC_Table.php

Lines 1447 to 1449 in 28c3779

	$db
	->prepare("UPDATE " . $this->strTable . " SET sorting=? WHERE id=?")
	->execute($count++ * 128, $objNewSorting->id);

contao/core-bundle/contao/drivers/DC_Table.php

Lines 1565 to 1567 in 28c3779

	$db
	->prepare("UPDATE " . $this->strTable . " SET sorting=? WHERE id=?")
	->execute($count++ * 128, $objNewSorting->id);

[aschempp]

First of all I'm not sure if this is really considered a bug or working as intended.

Marking this as up-for-discussion because I'm not sure either 😅