Re: query with bad performance after migration to mysql 5.6

[Øystein Grøvlen]

Hi Walter,

In order to understand better what is going on here, it would be useful if you could provide optimizer trace for this query in MySQL 5.6. (See https://dev.mysql.com/doc/internals/en/optimizer-tracing.html for information on how to generate the trace.) Also, the output of EXPLAIN FORMAT=JSON could be useful to understand how the sorting is performed.

Thanks,

Øystein Grøvlen,
Senior Principal Software Engineer,
MySQL Group, Oracle,
Trondheim, Norway