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Displaying posts with tag: Databases (reset)
When is a crashing MySQL bug not a bug?

Answer: When Oracle acknowledges the bug in 5.5.25 (to the owner only), corrects the bug in 5.5.27 (to the owner only), yet hides all information of its existence.

Recently a colleague and good friend discovered a bug in MySQL 5.5 replication that would crash MySQL. This was initially reported as Bug #65740, and after a lot of back and forth, a reproducible test case was found. Excellent work on the part of my colleague to spend the time to clearly identify the specific conditions. I remember looking at this initial thread in detail for an UPDATE statement using variables combined with an –ignore-database configuration option.

For no explanation by Oracle, this bug was subsequently marked as private (after I originally viewed the thread publicly), corrected, and the corrected bug is not referenced in the …

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Recent Presentations in Cali, Colombia

On July 4 I gave two presentations at the OTN Tour Day, and on July 5 I have three presentations at the MySQL Training Days. This was my 3rd visit to Colombia and it was great to see a receptive audience. Thanks to Robin for organizing the events in 2010, 2011 and 2012.

You can download all presentations from the provided links.

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Video interviews at OTN Colombia

The following are short interviews from the Oracle Technology Network (OTN) event in Cali, Colombia. One with myself and another with Sheeri Cabral.


These Videos are sourced from OTN Tour Latin America 2012.

NIST::NVD::Store::SQLite3 1.00.00

It’s been released. Use this with NIST::NVD 1.00.00 and you will be able to perform immediate look-ups of CVE and CWE data given a CPE URN. For instance:

cjac@foxtrot:/usr/src/git/f5/NIST-NVD-Store-SQLite3$ perl Makefile.PL ; make ; make test ; cjac@foxtrot:/usr/src/git/f5/NIST-NVD-Store-SQLite3$ perl -MNIST::NVD::Query -MData::Dumper -e '
$q = NIST::NVD::Query->new(store    => q{SQLite3},database => q{t/data/nvdcve-2.0.db});
$cve_list = $q->cve_for_cpe( cpe => q{cpe:/a:microsoft:ie:7.0.5730.11} );
print Data::Dumper::Dumper { cve_list => $cve_list, first_cvss => $q->cve( cve_id => $cve_list->[0] )->{q{vuln:cvss}} }
'
$VAR1 = {
          'cve_list' => [
                          'CVE-2002-2435',
                          'CVE-2010-5071'
                        ],
          'first_cvss' => {
                            'cvss:base_metrics' => { …
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New security fixes for MySQL reported

6 new security fixes for Oracle MySQL have been detailed in the most current Oracle Critical Patch Update (CPU).

These are:

  • CVE-2012-1735 (5.5.23 and earlier)
  • CVE-2012-0540 (5.1.62 and earlier, 5.5.23 and earlier)
  • CVE-2012-1757 (5.5.23 and earlier )
  • CVE-2012-1756 (5.5.23 and earlier)
  • CVE-2012-1734 (5.1.62 and earlier, 5.5.23 and earlier )
  • CVE-2012-1689 (5.1.62 and earlier, 5.5.22 and earlier )

Oracle strongly recommends that customers apply CPU fixes as soon as possible. Unfortunately there is no easy description for MySQL users what that really entails. There is a reference to Critical Patch Update July 2012 Patch Delivery Document for Oracle Sun Products Suite My Oracle Support Note 1446033.1, however all the information is behind …

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I will be speaking at Percona Live New York


Percona is back for a second New York Percona Live Conference. As the resident New York MySQL Expert, I will again be presenting. My session will be on MySQL Backup and Recovery Essentials.

You can only present so much in one hour, and this presentation just touches on the highlights of what is possible. More detailed information about the right backup and recovery strategy and associated tools is available in my current book Effective MySQL: Backup and Recovery.

Encrypting your MySQL backups and more

Assuming you have a backup and recovery strategy in place, how secure is your data? Does a hacker need to obtain access to your production system bypassing all the appropriate security protection you have in place, or just the unencrypted data on the backup server?

Encryption with zNcrypt

The following steps demonstrate how I setup a mysqldump encrypted backup with zNcrypt, a product from Gazzang. You can request a free trial evaluation of the software from http://gazzang.com/request-a-trial. I asked for a AWS EC2 instance, and was able to provide my bootstrap instructions for OS and MySQL installation. Following installation and configuration, the first step is to verify the zNcrypt process is running:

$ sudo ezncrypt-service status
  ezncrypt | Checking system dependencies
** ezncrypt system is UP and …
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What compression do you use?

The following is an evaluation of various compression utilities that I tested when reviewing the various options for MySQL backup strategies. The overall winner in performance was pigz, a parallel implementation of gzip. If you use gzip today as most organizations do, this one change will improve your backup compression times.

Details of the test:

  • The database is 5.4GB of data
  • mysqldump produces a backup file of 2.9GB
  • The server is an AWS t1.xlarge with a dedicated EBS volume for backups

The following testing was performed to compare the time and % compression savings of various available open source products. This was not an exhaustive test with multiple iterations and different types of data files.

Compression
Utility
Compression Time
(sec)
Decompression Time
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NIST::NVD 1.00.00

I’m leaving myself some room for bug fixes. It works for us in house. I would love to help others to give it a try. especially those who could benefit from making nearly immediately answered queries to the NIST’s NVD database.

The code in this release cannot by itself track the feed from the feds in real time. The nvd entry loader needs a little bit of love in the area of record merging before this starts working. It’s on my TODO list.

I’m sorry for the outage of git.colliertech.org. I’ll get that back up here shortly. In the meantime, feel free to grab it from this location while the CPAN indexes and processes my submission.

http://www.colliertech.org/federal/NIST/NIST-NVD-1.00.00.tar.bz2

don’t forget to check the cryptographic signature:

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Recent Presentations Buenos Aires MySQL/NoSQL/Cloud Conference

The first annual Latin America MySQL/NoSQL/Cloud Conference was held in Buenos Aires Argentina from June 26-28. Kudos to Santiago Lertora from Binlogic who had the vision for the conference in his country and made it happen. I look forward to the second annual event.

My first presentation was “Improving Performance with Better Indexes”. This presentation details the six steps to SQL performance analysis, Capture, Identify, Confirm, Analyze, Optimize and Verify. An explanation of MySQL EXPLAIN, and working examples to create indexes and better covering indexes in several examples are provided. A production example of a 13 table join is used to detail how covering indexes and partial column indexes can make a dramatic improvement in performance. …

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