MySQL Bugs: #78744: COMMENT='MERGE_THRESHOLD=X' in a table comment is a poor design

Bug #78744	COMMENT='MERGE_THRESHOLD=X' in a table comment is a poor design
Submitted:	7 Oct 2015 23:07	Modified:	14 Oct 2015 16:02
Reporter:	Daniel Black (OCA)	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Server: InnoDB storage engine	Severity:	S3 (Non-critical)
Version:	5.7.6	OS:	Any
Assigned to:		CPU Architecture:	Any
Tags:	innodb, MERGE_THRESHOLD

Description:
http://dev.mysql.com/doc/refman/5.7/en/index-page-merge-threshold.html describes setting MERGE_THRESHOLD in the comment field of a table.

Table definitions already use an extensive key=value syntax for tables.

Comments are current used for well, user space defined comments and not table options.

How to repeat:
CREATE TABLE t1 (
   id INT,
  KEY id_index (id)
) MERGE_THRESHOLD=45, COMMENT='this is a table for t1 data and not a configuration option';

syntax error

Suggested fix:
Use a proper syntax and remove the setting of COMMENT='MERGE_THRESHOLD'

CREATE TABLE t1 (
   id INT,
  KEY id_index (id)
) MERGE_THRESHOLD=45;

Agreed!!!  +1

Hi Daniel,

I do not like to comment on design or verify bugs dealing with design details, but I must admit that I agree with you on this one !!!

Verified as reported !!!

This design was introduced in WL#6747. I opposed to it, and the response was to file WL#8146 to implement the MERGE_THRESHOLD properly as SQL syntax. I hope that it can be done properly in the next major MySQL version.