The latest from the MySQL community

One problem I have experienced during logical exporting and importing databases is the tools don’t output any progress indicator (or anything at all really) and using the -v (verbose) switch outputs every single MySQL command being run from the import file. As, importing and exporting of databases  is one of the most frequent activity being performed , I Just felt the need of some tool that could help me check the approximate progress of import and export of databases going on.

So, I searched and fortunately could find a tool named Pipeviewer (PV) which allows a user to see the progress of data through a pipeline, by giving information such as time elapsed, percentage completed (with progress bar), current throughput rate, total data transferred, and ETA .

Installation :

On Centos and RHEL :

[root@vm1 vagrant]# yum install pv

[root@vm1 …

As a MySQL database administrator, we all using the MySQL client program for communicate to MySQL Server . Maximum the client program is used to execute the SQL’s, monitor the traffic and modify the variables . MySQL client program has some good features which can helps to make our work easier . In this blog I am going to explain some MySQL client program features which impressed me .

• Execute the OS commands inside the MySQL client program
• Create / Execute the SQL file inside the MySQL client program
• Query output with XML and HTML languages
• MySQL client program for learning MySQL commands .
• Pager with MySQL client program
• Safe UPDATE / DELETE with MySQL client program
• Define the maximum number of rows in result set ( SELECT’s )

Execute the OS commands inside the MySQL client program :

Yes, It is possible to execute …

Percona is happy to announce the experimental release of Percona XtraDB Cluster 8.0. This is a major step for tuning Percona XtraDB Cluster to be more cloud- and user-friendly. This is the second experimental release that combines the updated and feature-rich Galera 4, with substantial improvements made by our development team.

Improvements and New Features in Percona XtraDB Cluster

Galera 4, included in Percona XtraDB Cluster 8.0, has many new features. Here is a list of the most essential improvements:

• Streaming replication to support large transactions
• The synchronization functions allow action coordination (wsrep_last_seen_gtid, wsrep_last_written_gtid, wsrep_sync_wait_upto_gtid)
• More granular and improved error logging. wsrep_debug is …

Today we will see how to install WordPress in Oracle Cloud (OCI).

We will use Oracle Cloud’s Free Trier and deploy 2 compute instances:

• the webserver (apache, PHP and WordPress)
• the database server (MySQL 8.0)

We will use one public IP to reach our site and our two servers will communicate using their own private network:

Deploying 2 compute instances

Let’s start by creating 2 compute instances:

We will use the Oracle Linux 7.7 on Micro Instances:

As I am in Belgium, I use the Frankfurt datacenter.

When our instances are deployed, we can find the public IP of one of them. This is the one we will use as webserver (you can free the public IP on the other one, the MySQL one):

At the creation, we entered a ssh key to access …

How to Audit only DML Actions ?
Step by step to Enable Fine Grained MySQL Auditing for Insert/Update/Delete Queries for all Users.
Before i talk about MySQL Audit Filtering , it is more important to know below details:-

• What is MySQL Enterprise Audit ?
• Features of MySQL Audit.
• Why Audit is Important?
•  How to Audit only DML statements for Particular/All Users ?
• Audit Log Restrictions
• Conclusions

What is MySQL Enterprise Audit?

At high level, database auditing is the process to guard against misuse of information, track the use of database resources and activity like

-Who accessed the database(Users)

- Where these queries has been executed(Host Name).

-What kind of queries has been executed to db(events/statements).

-When did this happened(Time)

Few months back , I came to know about the tool Binlog2sql . The tool has very cool features like .

• The tool can extract SQL’s from MySQL Binary log .
• The tool can generate the rollback SQL’s for PITR .

In this blog, I am going to explain, how the above two features can be achieved using the tool binlog2sql .

Installation :

The tool has been developed by Mr. Cao Danfeng . Great Job Mr. Cao Danfeng . The tool can be downloaded from the GitHub .

https://github.com/danfengcao/binlog2sql

git clone https://github.com/danfengcao/binlog2sql.git

cd binlog2sql

pip install -r requirements.txt

Make sure, the …

Database schema change is becoming more frequent than before, Four out of five application updates(Releases) requires a corresponding database change, For a DBA schema change is a more often a repetitive task, it might be a request from the application team for adding or modifying columns in a table and many more cases.

MySQL supports online DDL from 5.6 and the latest MySQL 8.0 supports instant columns addition.

This blog post will look at the online DDL algorithms inbuilt which can be used to perform schema changes in MySQL.

DDL Algorithms supported by InnoDB is,

• COPY
• INPLACE
• INSTANT ( from 8.0 versions)

INPLACE Algorithm:

INPLACE algorithm performs operations in-place to the original table and avoids the table copy and rebuild, whenever possible.

If the INPLACE algorithm is specified with the …

This blog is about one of the issues encountered by our Remote DBA Team in one of the production servers. We have a setup of MySQL 5.7 Single Primary (Writer) GR with cluster size of  3 . Due to OOM, the MySQL process in the primary node got killed, this repeated over the course of the time.

We all know about the OOM (out of memory), theoretically, it is a process that the Linux kernel employs when the system is critically low on memory.

In a dedicated DB server, when the OOM triggers the direct impact will be on mysqld process since it will be the most memory consuming one.

Going forward will look into the detailed analysis made to tackle the issue of OOM.

DB Environment:-

• Service – Group Replication Cluster
• Cluster Nodes – 3
• GR mode – Single Primary …

Your application should retry the update or roll back. InnoDB is not losing atomicity. You commit a transaction with changes and that os just a bug in your app. Note that InnoDB always rolls back whole transactions on deadlock. Your application has to handle failed statements.

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The blog title seems something crazy ?

Yes, by default your InnoDB transactions don’t have the Atomicity . But, you can control the atomicity of your InnoDB transaction with the variable innodb_rollback_on_timeout. We had a weird data inconsistency issue within the transaction . In this blog , I am going to explain “How it will happen?” and “How it can be fixed ?” .

Whats is Atomicity ?

From Wiki ,

Transactions are often composed of multiple statements. Atomicity guarantees that each transaction is treated as a single “unit”, which either succeeds completely, or fails completely: if any of the statements constituting a transaction fails to complete, the entire transaction fails and the database is left unchanged.

What is …