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Search Results for: mysql row to column

Webinar: Building a highly scaleable distributed row, document or column store with MySQL and Shard-Query

On Friday, February 15, 2013 10:00am Pacific Standard Time, I will be delivering a webinar entitled “Building a highly scaleable distributed row, document or column store with MySQL and Shard-Query” The first part of this …


Why base64-output=DECODE-ROWS does not print row events in MySQL binary logs

Lately I saw many cases when users specified option --base64-output=DECODE-ROWS  to print out a statement representation of row events in MySQL binary logs just to get nothing. Reason for this is obvious: option --base64-output=DECODE-ROWS  does …


MySQL indexing 101: a challenging single-table query

We discussed in an earlier post how to design indexes for many types of queries using a single table. Here is a real-world example of the challenges you will face when trying to optimize queries: …


Optimizer hints in MySQL 5.7.7 – The missed manual

In version MySQL 5.7.7 Oracle presented a new promising feature: optimizer hints. However it did not publish any documentation about the hints. The only note which I found in the user manual about the hints …


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 …


Checking table definition consistency with mysqldiff

Data inconsistencies in replication environments are a pretty common. There are lots of posts that explain how to fix those using pt-table-checksum and pt-table-sync. Usually we only care about the data but from time to …


Advanced JSON for MySQL

What is JSON JSON is an text based, human readable format for transmitting data between systems, for serializing objects and for storing document store data for documents that have different attributes/schema for each document. Popular …


‘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 …


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 …


Identifying useful info from MySQL row-based binary logs

As a MySQL DBA/consultant, it is part of my job to decode the MySQL binary logs – and there are a number of reasons for doing that. In this post, I’ll explain how you can …