Emergency

Search Results for: update large database

Checking for a live database connection considered harmful

It is very common for me to look at a customer’s database and notice a lot of overhead from checking whether a database connection is active before sending a query to it. This comes from …

Read More
 

MongoDB Approach to database synchronization

I went to MongoSF today – quite an event, and I hope to have a chance to write more about it. This post is about one replication problem and how MongoDB solves it. If you’re …

Read More
 

When should you store serialized objects in the database?

A while back Friendfeed posted a blog post explaining how they changed from storing data in MySQL columns to serializing data and just storing it inside TEXT/BLOB columns. It seems that since then, the technique …

Read More
 

How clustering indexes sometimes help UPDATE and DELETE performance

I recently posted a blog entry on clustering indexes, which are good for speeding up queries. Eric Day brought up the concern that clustering indexes might degrade update performance. This is often true, since any …

Read More
 

Tradeoffs: Updates versus Range Queries

Sorry for the delay, now on to range queries and lenient updates. Let’s call them queries and updates, for short. So far, I’ve shown that B-trees (and any of a number of other data structures) …

Read More
 

Finding out largest tables on MySQL Server

Finding largest tables on MySQL instance is no brainier in MySQL 5.0+ thanks to Information Schema but I still wanted to post little query I use for the purpose so I can easily find it …

Read More
 

PHP Large result sets and summary tables.

We’re working with web site preparing for massive growth. To make sure it handles large data sets as part of the process we work on generation test database of significant size as testing your application …

Read More
 

ObjectRocket’s David Murphy talks about MongoDB, Percona Live Amsterdam

Say hello to David Murphy, lead DBA and MongoDB Master at ObjectRocket (a Rackspace company). David works on sharding, tool building, very large-scale issues and high-performance MongoDB architecture. Prior to ObjectRocket he was a MySQL/NoSQL …

Read More
 

MySQL is crashing: a support engineer’s point of view

In MySQL QA Episode #12, “MySQL is Crashing, now what?,” Roel demonstrated how to collect crash-related information that will help Percona discover what the issue is that you are experiencing, and fix it. As a Support …

Read More
 

The MySQL query cache: Worst enemy or best friend?

During the last couple of months I have been involved in an unusually high amount of performance audits for e-commerce applications running with Magento. And although the systems were quite different, they also had one …

Read More