Bug #69358 Table Index/Foreign Key Limit of 64 Keys - Only fixable with OS level access
Submitted: 30 May 2013 23:42 Modified: 24 Jun 2013 18:51
Reporter: Adam Adair Email Updates:
Status: Verified Impact on me:
None 
Category:MySQL Server: InnoDB storage engine Severity:S4 (Feature request)
Version:5.7 OS:Any
Assigned to: CPU Architecture:Any
Tags: 64 Limit, foreign key, INDEX KEY, table

[30 May 2013 23:42] Adam Adair
Description:
Curently there is a limit of 64 keys on an InnoDB Table. I know this can be fixed by recompiling or OS level command lines, however situations where this level of access isn't avaliable (say Amazon AWS MySQL offering) its not possible to increase the default from 64.

I wish to request the default be increased to preferably 256 and a feature added so the key limit can be increased by using a SQL command line (at the SQL level). Like the way Foreign Key Checks are enabled or disabled with an SQL Statement.

How to repeat:
Create an InnoDB Table and then try to create more then 64 keys - this shows the limit.

Try to increase the limit from the SQL level and its not possible. (Must have OS level access to increase this limit).

Suggested fix:
Increase the default number of InnoDB keys per table from 64 to 256.

Create an SQL Statement that can be used to alter the number of Keys usable so this can be updated on the fly.
[24 Jun 2013 18:51] MySQL Verification Team
Thank you for the bug report.