I would like to highlight some of the changes.
There are over a hundred bug fixes and big thanks to Hope Lee, Casa Zhang, Øystein Grøvlen, Song Zhibai, Facebook, Hobert Lu, Brian Yue, Zhai Weixiang, Murakami Kohei, Venkatesh Prasad Venugopal, and the Tencent team.
This release does not have a lot of 'wow' new features but shows a lot of solid work in evolving the product.
- The new audit_log_disable system variable permits disabling audit logging for all connecting and connected sessions.
- The output from EXPLAIN FORMAT=TREE was ex-encoded ranges for multi-valued indexes Now, hex-encoding is used only for string types having a binary character set. Strings with non-binary character sets are now printed as plain text, with escaping for any special characters.
- Now, hex-encoding is used only for string types having a binary character set. Strings with non-binary character sets are now printed in EXPLAIN FORMAT=TREE output as plain text, with escaping for any special characters.
- The shortcuts ASCII for CHARACTER SET latin1 and UNICODE for CHARACTER SET ucs2 are now deprecated, and you should expect their removal in a future version of MySQL. Using either of these now raises a warning; use CHARACTER SET instead.
- The character sets ucs2, macoman, macce, dec, and hp4 along with all of their collations, are now deprecated, and subject to removal in a subsequent release of MySQL. You should use utf8mb4 instead of any of the character sets just listed.
- The GnuPG build key used to sign MySQL downloadable packages has been updated. The previous GnuPG build key is set to expire on 2022-02-16. For information about verifying the integrity and authenticity of MySQL downloadable packages using GnuPG signature checking, or to obtain a copy of our public GnuPG build key, (Yup, it took a little while to get the new key out there when '28 was first published -- appologies!)
- A new Performance Schema statement metric, CPU_TIME, is now available, enabling you to measure the CPU time spent on a query.
- The number of distinct windows which can appear in a given SELECT is now limited to 127. The number of distinct windows is the sum of the named windows and the implicit windows specified as part of any window function's OVER clause. In order to use a large number of windows, it may be necessary to increase the value of the thread_stack server system variable. (Not sure just how you count the number of implicit windows!) UPDATE from Justin Swanhart - I was reading your latest blog post. In a query each window function that uses OVER which does not use a named window is an implicit window. If all of your window functions are framed the same they can share a named window, and you can have basically unlimited window functions. But if you use OVER for each of them, then you are limited to 127.
So, please download this new version ASAP.