Monday, April 27, 2020

MySQL 8.0.20 Is Released

MySQL 8.0.20 was released April 27th. So what  is new? The details are in the release notes and I would like to point out a few of the more interesting things, at least to me.

New SHOW_ROUTINE privilege 

Previously those using routines had to had the SELECT privilege which in many cases was overly broad. So for better granularity and control of resources.


To bring JSON_TABLE into compliance with the specification, ON EMPTY must now come before ON ERROR where in previous versions you could the two clauses in any way you wanted.

Hash Joins

Hash joins are now available as Inner non-equi-joins, Semijoins, Antijoins, Left outer joins, and
Right outer joins.

Double Buffer Improvement

The InnoDB storage engine area for the doublewrite buffer was moved from the system tablespace to doublewrite files.This reduces write latency, increases throughput, and provides flexibility with respect to placement of doublewrite buffer pages.

Binary Log Compression

You can now use the zstd algorithm with replication! The log files are not decompressed by receiver threads and are written to the relay log still in their compressed state. This compression  saves storage space both on the originator of the transaction and on the recipient and saves network bandwidth when the transactions are sent between instances.

Bugs Gone

I counted 248 bugs fixed.