A a new tracing capability has been added to the MySQL optimizer with 5.6.3. Optimizer Tracing goes beyond EXPLAIN EXTENDED to show how the optimizer treats queries. The demonstration of this feature at Oracle Open World had several noted DBAs speechless.

SET optimizer_trace="enabled=on";
SELECT Name FROM City WHERE ID=999;
SELECT trace into dumpfile '/tmp/foo' FROM INFORMATION_SCHEMA.OPTIMIZER_TRACE;

And the trace follows (sadly WordPress kills the indentations, PDF of trace here)


{
"steps": [
{
"join_preparation": {
"select#": 1,






Today we will get MySQL Cluster running on a single node.

A few years ago I created as presentation on running MySQL Cluster 5.1 on a laptop using Virtualbox that has proven to be the most popular download from NorthTexasMySQL.org with over nine hundred downloads.  Now MySQL 7.2 is in development milestone release and I find that I have some catching up to do.

Those of you with access to the Carrier Grade Edition (CGE) of Cluster, check out MySQL Cluster Manager 1.1 and Andrew Morgan’s  blog.  You can set up a cluster with minimal editing of configuration files or perform online software upgrades.

But MySQL Cluster 7.2 from