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Query attributes have in a long time been used to add metadata to queries to provide additional context such as where in the application the query was generated. The traditional way to do this is to add a comment at the start of the query with the attributes. Since the MySQL parser ignores the comment, it does not change the semantics of the query, but various tools can extract the comments.

This post looks into the reasons for using query attributes, how it is done using a comment, and the new component for MySQL 8.0.23 that provides native support for query attributes.

Advice

Query attributes are also known as query tags.

Why Query Attributes?

At the surface, it may seem that there is no major benefit from having metadata …

We recently saw how the new Invisible Column feature works in MySQL since 8.0.23 and how we can use it as a Primary Key for InnoDB tables when no Primary Key was defined.

As I wrote earlier, a good Primary Key is important for InnoDB (storage, IOPS, secondary indexes, memory…) but there is another important domain where a Primary Key is important in MySQL: replication !

Asynchronous Replication

When using “traditional” replication, if you modify a record (UPDATE and DELETE), the record(s) to modify on the replica are identified using indexes, and of course the Primary Key if any. The hidden global 6-bytes auto generated by InnoDB primary key is never used as never exposed and as it’s global, …

This article is the second part of the series related to MySQL Invisible Column started here.

This post covers why Invisible Column is important for InnoDB Storage Engine.

To start, let me explain briefly how InnoDB deals with Primary Key and why an good primary key is important. And finally, why having a Primary Key is also important.

How does InnoDB Stores Data?

InnoDB stores data in table spaces. The records are stored and sorted using the clustered index (the primary key): they are called index-organized tables.

All secondary indexes also contain the primary key as the right-most column in the index (even if this is not exposed). That means when a secondary …

With the new MySQL 8.0.23, something very interesting has been released: Invisible Column.

This is the first post dedicated to this new feature, I expect to write a series of 3. This one is the introduction.

Prior to MySQL 8.0.23, all columns of a table were always visible (if you had the privilege to see it). Now, an invisible column can be specified and will be hidden to queries. It can always be accessed if explicitly referenced.

Let’s see how it works:

create table table1 (
   id int auto_increment primary key, 
   name varchar(20), 
   age int invisible);

In the table description we can see the INVISIBLE keyword in the Extra column:

desc table1; …

The expected version 8.0.23 of MySQL has been released yesterday \o/

For new features and resolved bugs, I recommend Geir‘s traditional blog post announcing the release.

Of course, as usual, this release contains contributions from our great Community and let me thanks all the contributors on behalf of the MySQL Team.

MySQL 8.0.23 includes contributions from Daniel Black, Vilnis Termanis, Venkatesh Prasad Venugopal, Daniël van Eeden, Cai Yibo, Kamil Holubick, Shaohua Wang, Krunal Bauskar, Tzachi Zidenberg, Cédric Luthi, Brian Yue, Hope Lee and Facebook.

Thank you all for your great contributions. MySQL is an Open Source project, GPL, …

If you plan to deploy a Drupal site to OCI using MySQL Database Service, there is a very easy way to perform that deployment: using OCI’s Resource Manager !

As you know, security is something very important for Oracle in OCI, therefor, exposing the database on the Internet is not allowed.

Even if you are not using OCI, I really recommend you to follow that principle and never expose your database to Internet !

I already cover this in many previous posts. But I also understand that for people not being a sysadmin, this can be complicated the first time.

That’s why, all this can be automated using a stack to deploy in Resource Manager.

The first thing to do when you have your OCI account, it’s to download the stack from GitHub: https://github.com/lefred/oci-drupal-mds

Then in OCI’s dashboard, just …

We have many ways to install MySQL on linux machines such as source, binary and so on. But most of the Engineers always prefer default package managers (yum for RPM-Based distributions and apt for DPKG-Based distributions) for its ease of use and it can resolve all dependencies on its own. And of course, it is not possible to use package managers in environments where the internet is not allowed, but this is a different case. 

At some point, we need to install exactly specific version of MySQL for the following cases

• To create Production Replicas 
• To simulate an Production Issue on similar kind of environment
• To configure Disaster Recovery(DR)/UAT Setup
• Compatibility with opensource tools ( Eg , …

Magento is a very popular e-commerce platform using MySQL as backend.

The latest version is compatible with MySQL 8.0, however it’s not that easy to deploy. Magento has multiple dependencies like Elasticsearch for example. Additionally, the Open Source version seems to require Highly Technical knowledge to be deployed correctly.

If you would like to test it with MySQL Database Service (MDS) in OCI, you can find a stack file on this GitHub repository that easily deploys everything you need.

After applying the Stack in OCI’s Resource Manager, you have a brand new Magento ready to use !

Let’s see this in action:

As you could see this is very easy. Enjoy MySQL Database Service on OCI and I’m always please to …

Recently (earlier today), I blogged about how to use PHPMyAdmin with a MDS instance. I also showed at the end of the video that it’s possible to open MySQL Router on the compute instance to connect from anywhere. However this has security risks of course. Therefor, it’s not recommended.

If you want to connect from on-premise to your MDS instance you should use a VPN or a SSH tunnel. Take a look at these previous post:

• https://lefred.be/content/migrate-from-on-premise-mysql-to-mysql-database-service/
• …

I recently received several messages from developers not being comfortable with command line when they need to create schemas, tables, … They were asking me for an easy alternative when testing MDS.

There is a very popular tool in the developer community to manage their databases in MySQL: PHPMyAdmin.

So if you are trying MDS (MySQL Database Service in Oracle Cloud Infrastructure), it’s possible to deploy such instance with a compute instance hosting PHPMyAdmin very easily using OCI’s Resource Manager and a stack (zip file) that you can find here: https://github.com/lefred/oci-phpmyadmin-mds/releases/tag/1.1.0

If you want to try MDS in OCI, you can get free credits using this url: …