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Search Results for: table joins

Optimizing PXC Xtrabackup State Snapshot Transfer

State Snapshot Transfer (SST) at a glance PXC uses a protocol called State Snapshot Transfer to provision a node joining an existing cluster with all the data it needs to synchronize.  This is analogous to …

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Speed up GROUP BY queries with subselects in MySQL

We usually try to avoid subselects because sometimes they force the use of a temporary table and limits the use of indexes. But, when is good to use a subselect? This example was tested over …

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Auditing MySQL with McAfee and MongoDB

Greetings everyone! Let’s discuss a 3rd Party auditing solution to MySQL and how we can leverage MongoDB® to make sense out of all of that data. The McAfee MySQL Audit plugin does a great job of …

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‘Indexing’ JSON documents for efficient MySQL queries over JSON data

MySQL meets NoSQL with JSON UDF I recently got back from FOSDEM, in Brussels, Belgium. While I was there I got to see a great talk by Sveta Smirnova, about her MySQL 5.7 Labs release …

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Diagnosing SST errors with Percona XtraDB Cluster for MySQL

State Snapshot Transfer (SST) is used in Percona XtraDB Cluster (PXC) when a new node joins the cluster or to resync a failed node if Incremental State Transfer (IST) is no longer available. SST is …

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Percona XtraDB Cluster 5.6.19-25.6 is now available

Percona is glad to announce the new release of Percona XtraDB Cluster 5.6 on July 21st 2014. Binaries are available from downloads area or from our software repositories. We’re also happy to announce that Ubuntu …

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Q&A: Even More Deadly Mistakes of MySQL Development

On Wednesday I gave a presentation on “How to Avoid Even More Common (but Deadly) MySQL Development Mistakes” for Percona MySQL Webinars.  If you missed it, you can still register to view the recording and my slides. Thanks …

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Parallel Query for MySQL with Shard-Query

While Shard-Query can work over multiple nodes, this blog post focuses on using Shard-Query with a single node.  Shard-Query can add parallelism to queries which use partitioned tables.  Very large tables can often be partitioned fairly …

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Finding a good IST donor in Percona XtraDB Cluster 5.6

Gcache and IST The Gcache is a memory-based cache of recent Galera transactions that is local to each node in a cluster.  If a node leaves and rejoins the cluster, it can use the gcache …

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Designing one to many relations – MongoDB vs MySQL

We already discussed one to one relations in MongoDB, and the main conclusion was that you should design your collections according to the most frequent access pattern. With one to many relations, this is still …

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