Thank you to everyone who joined us for the 19th edition of MyWebinar. We hope that our time together helped to elevate and seam your work to perfection. We’re committed to giving back to the opensource database community in the coming days by presenting more LIVE events.

Recently, Mydbops conducted a webinar on the top 10 features of MySQL 8. MySQL is one of the most popular and widely used open-source relational database management systems. With every new version, MySQL brings new features and enhancements that make it more reliable, secure, and efficient. In this blog, we will wrap up the top 10 features of MySQL 8 discussed in the webinar by Mydbops.

Vinoth Kanna, co-Founder from  …

The Primary key is like the hero of a row, which has more beneficial features in the table while performing any task on the table.

The DBA knows the importance of the primary key in the table and how to handle it.

1. Notable features of having a primary key:
2. Requirements:
3. Enabling GIPK:
4. Handling GIPK:
…

We’re ecstatic and energised about the prospect of sowing seeds of knowledge in our opensource database community.

Thank you to everyone who joined us for the 17th edition of MyWebinar. We hope that our time together helped to elevate and seam your work to perfection. We’re committed to giving back to the opensource database community in the coming days by presenting more LIVE events.

Maha Lakshmi Ganapathineedi from Mydbops was successful in making this event more interactive, engaging, and, most importantly, productive for the audience. Thank you for your continuous contribution to the opensource community.

Topic: Redo …

MySQL 8.0.30 was released on 26-07-2022. It has a good list of features.

• Generated Invisible Primary Key
• Dynamic Redo log Sizing
• Instruments to monitor group replication memory
• Support for Ubuntu 22.04

A most notable feature for Database Administrators and database reliability engineers is Dynamic redo logging.

The more widely adopted open-source backup tool is Xtrabackup. The change in the redo log design has affected this hot backup tool.

2022-10-04T18:40:08.211998+05:30 0 [Note] [MY-011825] [Xtrabackup] recognized server arguments: --datadir=/var/lib/mysql 
2022-10-04T18:40:08.212264+05:30 0 [Note] [MY-011825] [Xtrabackup] recognized client arguments: …

As a Database Engineer, One of the biggest challenges in day-to-day activity is performing DDL on high-traffic and transaction-intensive tables. It will become overhead when handling a large number of servers/shards.

As a standard process, we will first deploy the changes in DEV and QA before deploying them in production.

In the sharded environment, It will become a heavy overhead to maintain the schema changes in DEV, QA, and PROD servers. Since we will have multiple servers in the sharding.

To overcome this deployment supervision, the Skeema tool will help to deploy the changes in QA, DEV, and PROD in a safe and parallel ( for Shards ) as well.

This blog focuses on the basic operation of Skeema, will have a series of blogs on Skeema

1. About the …

This is one of the exciting troubleshooting related to XA transactions let’s dive in. Let me provide a few backgrounds.

For one of our clients, when we try to drop a table, it is waiting for metadata lock. On debugging it is one of the XA transactions is holding the shared write lock and causing metadata lock on all the other local transactions.

Let us view the metadata locks from the Performance Schema.

Amazon Web Services (AWS) very recently(March 02, 2022) announced the GA of its new RDS feature “Readable standby with Multi-AZ deployments” for MySQL. Yes !! you heard it right you can now use the standby instances created with Multi-AZ deployments for failover as well as for Read-scaling starting with version 8.0.26 and later for MySQL in RDS

Launching a MultiAZ Cluster

Now let us see how to launch this readable-Multi AZ cluster?

Region Availability: As this is a new feature now it is currently limited to the regions US-EAST-1 (N.Virginia), US-WEST-1 (Oregon), and EU-WEST-1 (Ireland), this list would be extended progressively

VPC requirement:

Before launching the instance, you should have SUBNET created for 3 AZ(Availability Zone) within the VPC since the cluster instances would be spawn across 3AZ by default

Hereunder the “Engine Option” …

Rollback is an operation, which changes the current state of the transaction to the previous state. Undo logs are generally required if we want to roll back any of the uncommitted transactions and it plays a major role in Isolation.

For any changes made during a transaction, it must be stored priorly, because they are required if we choose to roll back the transaction.

Entries are made in undo logs when data modifications are done. If a transaction modifies data with SQL commands, It will create discrete undo logs for each operation. Once a transaction is committed MySQL is free to purge the undo logs created in that transaction. 

To know more about undo logs, you can check our previous blogs on overview to undo logs.

Usually, the Rollback process will take more time than the original operation. Because …

While exporting the table with MySQL native utility, we don’t have any control on the process, and also there will be no progress update as well on the process completion. So when exporting the larger table will consume high resource utilization and also the disk space usage will also be high.

MySQL shell utility will make the process easier. It will export the table and we can import the data back with a parallel thread and also will provide the current progress status on export/import progress.

util.exportTable() utility was introduced in Shell – 8.0.22 version, will export the data in a controlled manner. We can store the data in either local or Cloud Infrastructure Object Storage bucket as well.

We will see about the compression ratio along with the time taken for native MySQL vs Shell utility

Feature :

• Compression
• Progress status
• Supported output …

We all tried various alternative methods for modifying the table structure, but pt-online-schema-change (pt-osc) is the most convenient and preferred method for performing the alter online. It has more granular control too. But it may lead to data loss if proper precautionary steps are not taken care of.

In this blog, we are going to modify a column to a unique key using pt-osc, below I have shared the table structure.

mysql> show create table test\G
* 1. row *
Table: test
Create Table: CREATE TABLE test (
Personid int(11) NOT NULL AUTO_INCREMENT,
LastName varchar(255) NOT NULL,
FirstName varchar(255) DEFAULT NULL,
Age int(11) DEFAULT NULL,
PRIMARY KEY (Personid)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=latin1
1 row in set (0.00 sec)

I have inserted the data of 1000 rows using …