Emergency

Monthly Archives: January 2008

How MySQL Query Cache works with Transactions

As MySQL Manual Says Query Cache works with transactions with Innodb tables but it does not tell you how and with which restrictions. According to my tests it works but it is very restricted and …

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Monty unviels Maria and starts Blogging

This weekend we’re hearing great news from Michael “Monty” Widenius – one of the Fathers of MySQL. Monty finally found a time to create his own blog with very descriptive name Monty Says. At the …

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No more MySQL Crash Safe Replication in 5.0 ?

As you might know even if you’re only using Innodb tables your replication is not completely crash safe – if Slave MySQL Server crashes/power goes down it is likely for relay logs to run out …

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Enum Fields VS Varchar VS Int + Joined table: What is Faster?

Really often in customers’ application we can see a huge tables with varchar/char fields, with small sets of possible values. These are “state”, “gender”, “status”, “weapon_type”, etc, etc. Frequently we suggest to change such fields …

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Range Queries: Is the Bottleneck Seeks or Bandwidth?

Last time I talked about point queries. The conclusion was that big databases and point queries don’t mix. It’s ok to do them from time to time, but it’s not how you’re going to use …

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What should we say about Sun buying MySQL ?

Kaj wrote me email yesterday asking if I was sleeping for a whole week or may be dead because I’m probably the only one of people blogging about MySQL who has not commented about announced …

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The Trouble with Point Queries

Insertion and Queries Databases are complicated beasts, but I’d like to focus on the storage engine, just the part that talks to the storage system, and doesn’t have to worry about SQL, etc.: just transactions, …

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MySQL Blob Compression performance benefits

When you’re storing text of significant size in the table it often makes sense to keep it compressed. Unfortunately MySQL does not provide compressed BLOB/TEXT columns (I would really love to have COMPRESSED attribute for …

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PHP vs. BIGINT vs. float conversion caveat

Sometimes you need to work with big numbers in PHP (gulp). For example, sometimes 32-bit identifiers are not enough and you have to use BIGINT 64-bit ids; e.g. if you are encoding additional information like …

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CentOS Comes with free build of MySQL Enterprise ?

As I already wrote you can well go to Linux distribution vendors if you’re looking for recent MySQL version in a hassle free binary form. (On the time of this writing you could only get …

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