Bug #12207 alter table ... discard table space on MyISAM table causes ERROR 2013 (HY000):
Submitted: 27 Jul 2005 15:15 Modified: 1 Sep 2005 0:42
Reporter: Gleb Paharenko Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server Severity:S3 (Non-critical)
Version:5.0.9/BK source OS:Linux (Linux?windows)
Assigned to: Andrey Hristov 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: