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Search Results for: add column big table

Generated (Virtual) Columns in MySQL 5.7 (labs)

About 2 weeks ago Oracle published the MySQL 5.7.7-labs-json version which includes a very interesting feature called “Generated columns” (also know as Virtual or Computed columns). MariaDB has a similar feature as well: Virtual (Computed) Columns. The …

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Importing big tables with large indexes with Myloader MySQL tool

Mydumper is known as the faster (much faster) mysqldump alternative. So, if you take a logical backup you will choose Mydumper instead of mysqldump. But what about the restore? Well, who needs to restore a …

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When (and how) to move an InnoDB table outside the shared tablespace

In my last post, “A closer look at the MySQL ibdata1 disk space issue and big tables,” I looked at the growing ibdata1 problem under the perspective of having big tables residing inside the so-called shared …

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utf8 data on latin1 tables: converting to utf8 without downtime or double encoding

Here’s a problem some or most of us have encountered. You have a latin1 table defined like below, and your application is storing utf8 data to the column on a latin1 connection. Obviously, double encoding …

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Understanding the maximum number of columns in a MySQL table

This post was initially going to be two sets of polls: “What is the maximum number of columns in MySQL?” and “What is the minimum maximum number of columns in MySQL?”. Before you read on, …

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Tracking 5.3 Billion Mutations: Using MySQL for Genomic Big Data

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University of Montreal Tracks Genomic Data With Tokutek’s TokuDB. Faster insertion rates, improved scalability and agility support lab’s fast growing research database as it grows from 100s of GBs to 1 TB and beyond. Issue …

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Addressing Hot Schema Changes in MySQL

As ones data model evolves changing the database schema becomes painful, especially for big databases where the table must be taken offline. Fortunately, Tokutek introduced online schema changes starting in TokuDB v5.0. A typical schema change involves …

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Online Advertiser Intent Media Selects TokuDB over InnoDB and NoSQL for Big Data Ad-Hoc Analysis

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Intent Media Issue addressed: Ad hoc analytics on clickstream data arriving too fast for InnoDB or NoSQL to handle. TokuDB powers an online advertising application The Company: Headquartered in New York, Intent Media is a …

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Hot Column Addition and Deletion Part II: How it works

Hot Column Addition and Deletion (HCAD) In the previous HCAD post, I described HCAD and showed that it can reduce the downtime of column addition (or deletion) from 18 hours to 3 seconds. In fact, …

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Shard-Query adds parallelism to queries

Preamble: On performance, workload and scalability: MySQL has always been focused on OLTP workloads. In fact, both Percona Server and MySQL 5.5.7rc have numerous performance improvements which benefit workloads that have high concurrency. Typical OLTP …

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