Tag - kuzminsky

Checking B+tree leaf nodes list consistency in InnoDB

If we have InnoDB pages there are two ways to learn how many records they contain:

PAGE_N_RECS field in the page header
Count records while walking over the list of records from infimum to supremum

In some previous revision of the recovery tool a short summary was added to a dump which is produced by the constraints_parser.
But […]

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Finally. How to verify if all MySQL records were recovered

After nearly every recovery case the same question arises: How many MySQL records were recovered and how many were lost.
Until now there was no way to answer the question without manual investigation. As it turned out a small change can make a big difference.
There are two ways to know how many records an InnoDB […]

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How to recover table structure from InnoDB dictionary

To recover a dropped or corrupt table with Percona Data Recovery Tool for InnoDB you need two things: media with records(ibdata1, *.ibd, disk image, etc.) and a table structure. Indeed, there is no information about the table structure in an InnoDB page. Normally we either recover the structure from .frm files or take it […]

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