First steps on Kusto Query Language (KQL)

Do you know this query language?  No, it’s time to explain you and see what it is.

“A Kusto query is a read-only request to process data and return results.” dixit Microsoft Documentation here

The KQL is very simple to understand and use. I can do it then you can also do it!

The first thing to know is how to call the information on a table.

In this case you  need to call the table directly with the name of the table, in the place to do a SELECT * FROM Table.

Microsoft give us the opportunity to test it directly on Azure Data Explorer here

In my example, I will use the table Covid19 and I just write the name of the table to have all information:

Using the pipe (|) delimiter, I add filters, transformations etc…

My first test is to add a clause WHERE in the query:

I have all rows for Switzerland now.

When you begin, i advise you to take a look on the query best practices page and have directly the good practice here.

To filter on some columns, you need to add “Project” in the query:

The next step is to order the result and it’s easy with an “order by”

Very easy, it’s it!

The last step for this first approach is to present the result in a graph.

For this step, you will use the command render and with the intellisense, you have a lot of possibility

I choose the TimeChart to have the progression during the period:

Et voila, I do my first step in KQL!

Easy to understand, easy to learn, easy to use, easy to have a quick overview of your data…