databases Archive

pt-online-schema-change and partitions – a word of caution

Just a quick word of wisdom to those seeking to cleverly change the partitioning on a live table using a tool like pt-online-schema-change from the Percona Toolkit. You will lose data if you don't account for ALL of your data's ranges upfront. (E.g: MAXVALUE oriented partition). The reason being is how...
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Why are we spending so much time refuting?

There's a nice juicy war going on in the 'data / web' sector, that seems more heated than I can remember. It essentially boils down to sensationalist claims from the likes of MongoDB and MemSQL, which in turn draw refuting remarks from industry professionals that are typically embedded with RDBMS technologies. The...
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NoSQL: stretttcch – pop!

You know the noise you hear when something is stretched close to it's breaking point, like a balloon? In the context of the NoSQL bandwagon bubble: here's some of that noise. A detailed account of jumping on a bandwagon with an immature scene of products.Although admittedly I have my eye...
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MySQL – multibyte cheat sheet for conditionals

This is basically a short cheat sheet to launch some ideas for comparisons/matching with multibyte characters.Connection collation of utf8_unicode_ci and charset of utf8 - Table + data and server: [crayon-5c102b90465ae819251737/][crayon-5c102b90465b5733009436/][crayon-5c102b90465b7090794254/][crayon-5c102b90465ba106454779/]Check out the behavior of the following queries:[crayon-5c102b90465bc120776664/][crayon-5c102b90465bd333670169/]Other resources:MySQL's character sets and collations demystifiedMySQL charset documentationCharsets and joins (good gotcha to...
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Nay say for ext2/ext3, seemingly ext4 for MySQL servers

 Basically I felt compelled to make a note regarding what filesystem to evaluate when you are performing a MySQL install. There seems to be a lot of reasons NOT to use the ext filesystems, and instead use XFS..This is a straight out quote from a MySQL at Facebook blog entry:ext-2...
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Worthy of distribution: Reset root MySQL password

Oh snap! Need to reset your mysql root/admin (or any?) MySQL password? Well, you'll need root and control over MySQLd to some extent, but this is worthy of a rainy-day bookmark indeed: http://mysqlpreacher.com/wordpress/2011/03/recovering-a-mysql-root-password-three-solutions/ Subscribe in a reader...
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Programming through inductive reasoning

I'll never forget my Geometry class in high school, not just because it was fun, but the teacher was kind of an oddball (in a good kind of way). I learned so much from this class it was unbelievable, it was a life changing experience because it taught the true...
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Canonically speaking

A co-worker and I recently got into a discussion regarding table naming - specifically prefixes and how to group them.A common approach you see, is to group the tables around a system using a prefix for it's name:_newsevents_news_newsevents_categories_newsevents_aclThe hardest thing about keeping everything 'integrated' is to get other developer's off...
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