MySQL Forums :: MyISAM :: Undelete Rows
Re: Undelete Rows
Posted by: Ingo Strüwing ()
Date: February 01, 2007 04:21AM
Hi.
No. This is not possible. When a record is deleted, the start of each of its parts ("blocks") is overwritten with linkage information. All deleted parts of all records make a link or chain.
Hence the records cannot be restored in full.
In theory one could write a utility that follows the delete link. It could extract all non-overwritten parts of the records. They will even be in correct order. But it would be impossible to automatically determine where each record ends. That information was located at the start of the first part of a record, where it is now overwritten. Also it would be difficult to guess where each column starts when the start of the record is missing.
Regards
Ingo
Ingo Strüwing, Senior Software Developer - Storage Engines
MySQL AB, www.mysql.com
No. This is not possible. When a record is deleted, the start of each of its parts ("blocks") is overwritten with linkage information. All deleted parts of all records make a link or chain.
Hence the records cannot be restored in full.
In theory one could write a utility that follows the delete link. It could extract all non-overwritten parts of the records. They will even be in correct order. But it would be impossible to automatically determine where each record ends. That information was located at the start of the first part of a record, where it is now overwritten. Also it would be difficult to guess where each column starts when the start of the record is missing.
Regards
Ingo
Ingo Strüwing, Senior Software Developer - Storage Engines
MySQL AB, www.mysql.com
| Subject | Views | Written By | Posted |
|---|---|---|---|
| Undelete Rows | 15985 | Brian Connell | 01/22/2007 07:36AM |
| Re: Undelete Rows | 7942 | Brian Connell | 01/24/2007 04:38AM |
| Re: Undelete Rows | 8360 | Ingo Strüwing | 02/01/2007 04:21AM |
| Re: Undelete Rows | 7717 | Shane Bester | 02/09/2007 03:39PM |
| Re: Undelete Rows | 7185 | Shane Bester | 08/25/2007 05:28AM |
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