Tag - pt-online-schema-change

Rescuing a crashed pt-online-schema-change with pt-archiver

crashed pt-online-schema-change

This article discusses how to salvage a crashed pt-online-schema-change by leveraging pt-archiver and executing queries to ensure that the data gets accurately migrated. I will show you how to continue the data copy process, and how to safely close out the pt-online-schema-change via manual operations such as RENAME TABLE and DROP TRIGGER commands. The normal process […]

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pt-online-schema-change (if misused) can’t save the day

GTID replication

In this blog post we’ll discuss pt-online-schema-change, and how to correctly use it.
Always use pt-osc?
Altering large tables can be still a problematic DBA task, even now after we’ve improved Online DDL features in MySQL 5.6 and 5.7. Some ALTER types are still not online, or sometimes just too expensive to execute on busy production master.
So […]

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Testing MySQL partitioning with pt-online-schema-change

There are cases where we need to implement MySQL partitioning, or at least test if it is an option to solve an issue. However, how are we able to test it when the table on our production environment has hundreds of millions of rows, several composite indexes and/or the size on disk is hundreds of gigabytes?
Testing […]

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Schema changes in MySQL for OpenStack Trove users

People using OpenStack Trove instances can hit a common issue in the MySQL world: how to perform schema change operations while minimizing the impact on the database server? Let’s explore the options that can allow online schema changes.
Summary
With MySQL 5.5,

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Avoiding MySQL ALTER table downtime

Avoiding MySQL ALTER table downtime

MySQL table alterations can interrupt production traffic causing bad customer experience or in worst cases, loss of revenue. Not all DBAs, developers, and syadmins know MySQL well enough to avoid this pitfall. DBAs usually encounter these kinds of production interruptions when working with upgrade scripts that touch both application and database or if an […]

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