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Monthly Archives: April 2007

Back from RIT2007

So I’m back from RIT2007 which took place April 16,17 in Moscow,Russia. The conference was well organized, while the conference center was a bit small for event – halls were jam packed during the breaks …

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How simple answer are you looking for ?

I’ve got an interesting comment the other day saying “I’ve heard Jay Pipes saying indexes with cardinality lower than 30% are worthless, true?” That is interesting question and it has different answers depending on who …

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COUNT(*) vs COUNT(col)

Looking at how people are using COUNT(*) and COUNT(col) it looks like most of them think they are synonyms and just using what they happen to like, while there is substantial difference in performance and …

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PBXT benchmarks

The PBXT Storage Engine (http://www.primebase.com/xt/) is getting stable and we decided to benchmark it in different workloads. This time I tested only READ queries, similar to ones in benchmark InnoDB vs MyISAM vs Falcon (https://www.percona.com/blog/2007/01/08/innodb-vs-myisam-vs-falcon-benchmarks-part-1) …

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Master-Master or Master with Many Slaves

I just found post by Kevin, in which he criticizes Master-Master approach, finding Master with many slaves more optimal. There is surely room for master-N-slaves systems but I find Master-Master replication much better approach in …

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Using delayed JOIN to optimize count(*) and LIMIT queries

In many Search/Browse applications you would see main (fact) table which contains search fields and dimension tables which contain more information about facts and which need to be joined to get query result. If you’re …

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MySQL Master-Master replication manager released

The MySQL Master-Master replication (often in active-passive mode) is popular pattern used by many companies using MySQL for scale out. Most of the companies would have some internal scripts to handle things as automatic fallback …

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