Compatibility: annotate short-lived MySQL and MariaDB versions with EOL dates - #499

Fixes #433

Description

Adds end-of-life dates to the short-lived MySQL and MariaDB versions in the compatibility table, e.g. 12.2 (until 2026-05), so they no longer look current after upstream has dropped them.

Changes

compatibility.md:

• Added a sentence under the table intro explaining the (until YYYY-MM) format.
• Annotated every short-lived version in the WordPress 6.2 to 7.0 rows: MySQL Innovation releases, and MariaDB short-term and rolling releases. Long-term releases (MySQL 5.7, 8.0, 8.4, 9.7 and MariaDB LTS) keep no date.
• Split the mixed ranges in the 6.2 to 6.6 rows (e.g. 8.2 - 8.4, 10.10 - 11.1) into discrete versions so each short-lived one can be annotated. Ranges that contain only long-term releases (e.g. 10.4 - 10.6) stay as ranges.

Answers to the open questions in the issue thread

1. MariaDB 11.5 in the 6.7 and 6.8 rows is now annotated and split out of 11.4 - 11.5.

2. Versions that were already EOL on the WordPress launch date. The table intro defines the table as the versions "available (and security supported) at the time of the WordPress release", so these entries were wrong. This PR removes them and lists the short-lived release that was actually supported on the launch date:

One addition from the same check: MariaDB 11.2 (until 2024-11) is added to the 6.7 row. It was still supported on 2024-11-12, but the row skipped it.

3. MariaDB one-year short-term releases (10.7 to 10.10, 11.0 to 11.2) are annotated too. They had about a year of support and sit in the same ranges the issue asks to split, so leaving them bare would have them look current in the same way.

How this was checked

I checked every MySQL and MariaDB version in the 6.2 to 7.1 rows with a script against the endoflife.date data. For each row: every listed version was released on or before the launch date and still supported on it, no supported version is missing, and each until month matches the upstream EOL date. The 7.1 row already passed, so it is unchanged.

Notes

• Overlap with Compatibility: correct WordPress 6.2 and 4.1 launch dates #471: it changes the 6.2 launch date from 2023-03-28 to 2023-03-29, on the same table line, so whichever PR merges second needs a trivial rebase. The new date doesn't change the 6.2 versions.
• Overlap with Add WordPress 7.2 server compatibility documentation #494 (WP 7.2 page): that PR adds a 7.2 row with MySQL 26.7 and MariaDB 13.0, which are both short-lived. They have no fixed EOL date yet (supported until the next release ships), so I'll add the until month to that row once it is known, in whichever PR merges second.
• The per-version pages (version/7-0-compatibility.md, version/7-1-compatibility.md) already have Type and EOL columns, so they are not changed, as the issue says.
• No page was added and no title or path changed, so the manifest does not need regenerating.

Sources

• endoflife.date MySQL and MariaDB (API data pulled 2026-10-02)
• MariaDB maintenance policy
• MySQL Releases: Innovation and LTS
• Proposal: Clarifying Core's database support policy

AI Assisted: AI was used to help pull the EOL dates and cross-check the table.