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Search Results for: how fast can you sort data

Recovery beyond data restore

Quite frequently I see customers looking at MySQL recovery as on ability to restore data from backup which can be far from being enough to restore the whole system to operating state, especially for complex …

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Hacking for Faster Insertions: Is this really how you want to spend your time?

Recall that I’ve claimed that it takes 28 years to fill a disk with random insertions, given a set of reasonable assumptions. Recall what they are: We are focusing on the storage engine (a la …

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Speeding up GROUP BY if you want aproximate results

Doing performance analyzes today I wanted to count how many hits come to the pages which get more than couple of visits per day. We had SQL logs in the database so It was pretty …

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How Fast Can Updates Run?

Last time, I introduced the notion of strict and lenient updates. Now it’s time to see what the performance characteristics are of each. Just to rehash, we are focusing on the storage engine (a la …

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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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MySQL: Data Storage or Data Processing

I was thinking today of how people tend to use MySQL in modern applications and it stroke me in many cases MySQL is not used to process the data, at least not on the large …

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Possible optimization for sort_merge and UNION ORDER BY LIMIT

Every so often you need to perform sort results retrieved from MySQL when your WHERE clause goes beyound col=const values which would allow MySQL to still use second portion of the index for the order …

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Working with large data sets in MySQL

What does working with large data sets in mySQL teach you ? Of course you have to learn a lot about query optimization, art of building summary tables and tricks of executing queries exactly as …

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Predicting how long data load would take

I had this question asked many times during last week, and there is really no easy answer. There are just way too many variables to consider especially while loading large schemas with a lot of …

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Using Sphinx as MySQL data retrieval accelerator

I’ve run into the following thread couple of days ago: Basically someone is using sphinx to perform search simply on attributes (date, group etc) and get sorted result set and claiming it is way faster …

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