The latest from the MySQL community

In this post, I provide an illustration of how to use Pentaho Data Integration (PDI) tool to set up external dictionaries in MySQL to support ClickHouse. Although I use MySQL in this example, you can use any PDI supported source.

ClickHouse

ClickHouse is an open-source column-oriented DBMS (columnar database management system) for online analytical processing. Source: wiki.

Pentaho Data Integration

Information from the Pentaho wiki: Pentaho Data Integration (PDI, also called Kettle) is the component of Pentaho responsible for the Extract, Transform and Load (ETL) processes. Though ETL tools are most frequently used in data warehouses environments, PDI can also be used for other purposes:

• Migrating data between …

In this post, I provide an illustration of how to use Pentaho Data Integration (PDI) tool to set up external dictionaries in MySQL to support ClickHouse. Although I use MySQL in this example, you can use any PDI supported source.

ClickHouse

ClickHouse is an open-source column-oriented DBMS (columnar database management system) for online analytical processing. Source: wiki.

Pentaho Data Integration

Information from the Pentaho wiki: Pentaho Data Integration (PDI, also called Kettle) is the component of Pentaho responsible for the Extract, Transform and Load (ETL) processes. Though ETL tools are most frequently used in data warehouses environments, PDI can also be used for other purposes:

• Migrating data between …

Amazon RDS is a managed relational database service that makes it easier to set up, operate, and scale a relational database in the cloud. One of the common questions that we get is “What is Multi-AZ and how it’s different from Read Replica, do I need both?”.  I have tried to answer this question in this blog post and it depends on your application needs. Are you looking for High Availability (HA), read scalability … or both?

Before we go to into detail, let me explain two common terms used with Amazon AWS.

Region – an AWS region is a separate geographical area like US East (N. Virginia), Asia Pacific (Mumbai), EU (London) etc. Each AWS Region has multiple, isolated locations known as Availability Zones.

Availability Zone (AZ) – AZ is simply one or more data …

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With the introduction of MySQL Shell 8.0, the second major version of the new command-line tool for MySQL, a new and rich featured prompt was introduced. Unlike the prompt of the traditional mysql command-line client, it does not just say mysql> by default. Instead it comes in a colour coded spectacle.

The default prompt is great, but for one reason or another it may be that you want to change the prompt. Before getting to that, let’s take a look at the default prompt, so the starting point is clear.

The Default Prompt

An example of the default prompt can be seen in the screen shot below. As you can see, there are several parts to the prompt, each carrying its information.

…

Windowing Functions can get quite complex very quickly when you start taking advantage of the frame clause. Ranges and rows can get confusing.  So for review lets look at how the specification looks:

Window_spec:
   [window name] [partition clause] [order clause] [frame clause]

That looks simple. And them come terms like UNBOUNDED PRECEDING that could put a knot in your gut.  The manual is not exactly written to help novices in this area get up to speed.  But don't panic.  If you work through the examples that follow (and please do the preceding part of this series before trying these examples) you will have a better appreciation of what is going on with window function.

The Frame Clause
So the frame clause is optional in the window function.  A frame is considered a subset of the current partition and defines that subset.  Frames are determined with …

PMM (Percona Monitoring and Management) is a free and open-source platform for managing and monitoring MySQL and MongoDB performance. You can run PMM in your own environment for maximum security and reliability. It provides thorough time-based analysis for MySQL and MongoDB servers to ensure that your data works as efficiently as possible.

The most significant feature in this release is Prometheus 2, however we also packed a lot of visual changes into release 1.13:

• Prometheus 2 – Consumes less resources, and Dashboards load faster!
• New Dashboard: Network Overview – New dashboard for all things IPv4!
• New Dashboard: NUMA Overview – New Dashboard! …

In this blog post, we demonstrate how to convert a single standalone cluster into a Composite Primary/DR topology running in two data centers.

Our example starting cluster has 5 nodes (1 master and 4 slaves) and uses service name alpha. Our target cluster will have 6 nodes (3 per cluster) in 2 member clusters alpha_east and alpha_west in composite service alpha.

This means that we will reuse the existing service name alpha as the name of the new composite service, and create two new service names, one for each cluster (alpha_east and alpha_west).

Below is an INI file extract example for our starting standalone cluster with 5 nodes:

[defaults]
...

[alpha]
connectors=db1,db2,db3,db4,db5
master=db1
members=db1,db2,db3,db4,db5
topology=clustered

To convert the above configuration to a Composite Primary/DR:

1. First you must stop all services on all existing nodes:

   shell> stopall
   

   …

The main focus of a previous blog post was the performance of MyRocks when using fast SSD devices. However, I figured that MyRocks would be beneficial for use in cloud workloads, where storage is either slow or expensive.

In that earlier post, we demonstrated the benefits of MyRocks, especially for heavy IO workloads. Meanwhile, Mark wrote in his blog that the CPU overhead in MyRocks might be significant for CPU-bound workloads, but this should not be the issue for IO-bound workloads.

In the cloud the cost of resources is a major consideration. Let’s review the annual cost for the processing and storage …

From my past 2 posts, I have explained how to configure replication between CloudSQL to VM and VM to CloudSQL. Now we have implemented one more solution in CloudSQL is Configure replication between CloudSQL to another CloudSQL. Its almost similar to setting up the external Master. Lets see how to do this.

Where this will help you?

• Migrating from one project to different projects.
• Migrate the existing CloudSQL to Another Region.
• There is no straightforward ways shrink the MySQL volume(Some worst cases the auto increment added more space). So we can replicate it to another CloudSQL with less downtime.
…

Before I take up from the last blog, I need to introduce RANGE and ROWs.  Windows over data can be framed and this is where things can get wild and woolly.   Table x has a column named x (me being overly creative again) that has the values one through 10.  If we sum the values of x we can get different values depending on how the frame is constructed.

If the frame for the window is defined as a the range between 'unbounded preceding and current row' the value for the sum of x will the sum for the entire column of data.  However, if the frame is defined as the rows between 'unbounded preceding and current row' it will sum up the values of the current row and the values of the rows that came before; 1, 1+2, 1+2+3. etc.


mysql> SELECT x, sum(x) over w as 'rows',
    -> sum(x) over y as 'range'
  …