Search Results for: query mysql schema to find column

MySQL 5.7 key features

The other day I was discussing new features of MySQL 5.7 with a Percona Support customer. After that conversation, I thought it would be a good idea to compile list of important features of MySQL 5.7. The latest MySQL 5.7.6 release candidate (RC) is out and is packed with nice features. Here’s a list of […]

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 time we receive this question in support: How can I check the table definition consistency between servers? Replication also allow […]

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 document store databases use JSON (and the related BSON) for storing and transmitting data. Problems with JSON in MySQL It […]

‘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 JSON UDF functions. It is important to note that while the UDF come in a 5.7 release it is absolutely […]

MySQL 5.6 Transportable Tablespaces best practices

In MySQL 5.6 Oracle introduced a Transportable Tablespace feature (copying tablespaces to another server) and Percona Server adopted it for partial backups which means you can now take individual database or table backups and your destination server can be a vanilla MySQL server. Moreover, since Percona Server 5.6, innodb_import_table_from_xtrabackup is obsolete as Percona Server also […]

Sys Schema for MySQL 5.6 and MySQL 5.7

Performance Schema (P_S) has been available since MySQL 5.5, more than 4 years ago. It is still difficult to see production servers with P_S enabled, even with MySQL 5.6 where the feature is enabled by default. There have been several complaints like the overhead, that the fix is a work in progress, and the ease […]

How to deal with MySQL deadlocks

A deadlock in MySQL happens when two or more transactions mutually hold and request for locks, creating a cycle of dependencies. In a transaction system, deadlocks are a fact of life and not completely avoidable. InnoDB automatically detects transaction deadlocks, rollbacks a transaction immediately and returns an error. It uses a metric to pick the […]

Looking out for max values in integer-based columns in MySQL

Yay! My first blog post! As long as at least 1 person finds it useful, I’ve done my job. 😉 Recently, one of my long-term clients was noticing that while their INSERTs were succeeding, a particular column counter was not incrementing. A quick investigation determined the column was of type int(11) and they had reached […]

Getting to know TokuDB for MySQL

During last April’s Percona Live MySQL Conference and Expo, TokuDB celebrated it’s first full-year as an open source storage engine. I still remember reading the official announcement and the expectations it created one year ago. The premises were very interesting as it had the potential of helping MySQL manage “big data” in a way InnoDB just […]

Row-based replication, MySQL 5.6 upgrades and temporal data types

Whither your rollback plan? MySQL 5.6 upgrades are in full swing these days and knowing how to safely upgrade from MySQL 5.5 to 5.6 is important. When upgrading a replication environment, it’s important that you can build a migration plan that safely allows for your upgrade with minimal risk — rollback is often a very […]