(BC) Removed mysql4

[luigifab]

Description

This PR will hurt our feelings 💣 because it remove 99% of Mysql4 PHP class and the deprecatedNode XML node.
This will break 💥 many "outdated" modules.

There is a migration script: php shell/remove-mysql4.php
It will update all occurrences of mysql4 classes.

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All automated tests passed successfully (all builds are green)
• Add yourself to contributors list

[jfksk]

@addison74

what happens if an extension uses the mysql4 format?

The PR includes a migration script for that case

Has anyone performed a test for such a situation? Do we have to modify all extensions we currently use?

I tried it w/ two stores which are around since m1.3/m1.4 - with a good amount of mysql4 resources. The smaller code-base is definitively fine, the larger one needs more testing but I think it'll be fine too. I only used the migration script and didn't change anything manually - so far...

[jfksk]

In production for > 1 month

[kiatng]

Tested and worked for months now.

[addison74]

When there are so many changes involving dozens and even hundreds of files I think it would be best to break them into several PRs. I don't always have the ability to analyze modified files in an IDE and choose to do this task in the browser on my tablet.

I understand that everything can be done in a PR but when there are several pieces it is easier to do a reverse if issues occur. I personally agree with this change but I cannot approve it without intensive testing and modify the existing extensions I am using.

As a personal opinion such a PR should have a higher number of approvals to avoid further inconveniences and should be merged by a maintainer.

[fballiano]

I like this PR but:

• it needs a README section
• I'd rename the shell/rename-mysql.php script with a name that's a bit more verbose

[luigifab]

For readme, for what version?
For script name, rename-mysql4-class-to-resource.php ?

[fballiano]

right, we need another PR to modify the README in the v19 branch :-( that sucks... so... let's address it later but we should not forget it (actually we should put it in the release notes too)

I guess the "shell/" filename is ok, maybe I'll add a "-pr1470.php" suffix?

[midlan]

I like just rename-mysql4-class-to-resource.php
PR can be found easily by commit :)

[sreichel]

This should stay open.

[luigifab]

Sorry, too much conflicts.
I continue to use it.