MySQL Bugs: #71584: Optimizer executes statement inperformant

Bug #71584	Optimizer executes statement inperformant
Submitted:	4 Feb 2014 11:15	Modified:	29 Jun 2015 15:34
Reporter:	Martin Kirchner	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Optimizer	Severity:	S2 (Serious)
Version:	5.6.15 and 5.6.16	OS:	Linux (Debian 7.1)
Assigned to:		CPU Architecture:	Any

File:	Maximum allowed size is 50MB.
Description:
Privacy:

If the data you need to attach is more than 50MB, you should create a compressed archive of the data, split it to 50MB chunks, and upload each of them as a separate attachment.

To split a large file:

On *nix platforms use the split command e.g. split -b 50MB <my_large_archive> <my_split_archive_prefix>
On windows use WinZip or a similar utility to split the large file

Optimizer trace on LIVE - SubSelect - executed in 34 minutes

Attachment: live_trace_20140121_SubSelect_34min.txt (text/plain), 299.09 KiB.

Optimizer trace on LIVE - INNER JOIN - executed in 0,5s

Attachment: live_trace_20140203_InnerJoin_0s.txt (text/plain), 18.97 KiB.

Optimizer trace on TEST vm - INNER JOIN - executed in 50min

Attachment: testvm_trace_20140204_innerjoin_50min.txt (text/plain), 268.50 KiB.

Optimizer trace on TEST vm - SubSelect - executed in 1.5 minutes

Attachment: testvm_trace_20140204_subselect_1,5min.txt (text/plain), 247.04 KiB.

Execution plan of the subselect

Attachment: live_execution_plan_subselect_20140204_after_restart.txt (text/plain), 17.62 KiB.

Execution plan or the INNER JOIN (on live)

Attachment: live_execution_plan_innerJoin_20140204_after_restart.txt (text/plain), 16.24 KiB.

Trace of subselect on live

Attachment: live_trace_subselect_20140206_after_restart.txt (text/plain), 302.43 KiB.

Trace of inner join on live

Attachment: live_trace_inner_join_20140206_after_restart.txt (text/plain), 267.07 KiB.

Execution plan or the INNER JOIN (on test vm)

Attachment: testvm_execution_plan_innerjoin_20140206.txt (text/plain), 9.93 KiB.

Execution plan of the subselect (on test vm)

Attachment: testvm_execution_plan_subselect_20140206.txt (text/plain), 11.88 KiB.

Execution plan of EXISTS in tablerelation (on live)

Attachment: live_execution_plan_exists_tablerelation_20140207.txt (text/plain), 19.39 KiB.

Optimizer trace on LIVE - exists tablerelation - executed in 3,5s

Attachment: live_trace_exists_tablerelation_20140207_after_restart2.zip (application/x-zip-compressed, text), 72.53 KiB.