SQL Group By Month

Problem

Suppose we have a table containing employee information as shown below:

The goal is to order the data above based on the month of starting. This is described in the start_date column.

How can we approach such a problem?

The first method we can use is the extract() function in SQL. It allows us to extract specific parts from a date object.

Hence, we can use the extract() function to extract the month the date and group the data from the resulting value.

An example query is as shown:

SELECT
MAX(START_DATE)MAX(START_DATE)
FROM EMPLOYEES
GROUP BY EXTRACT(MONTH FROM START_DATE);

The above should group the data by the months and return the max date in each month group:

You can also use the date_format function to group data by the month name. An example is as shown:

SELECT DATE_FORMAT('month', START_DATE) AS START_MONTH,
COUNT (ID) AS ID
FROM EMPLOYEES
GROUP BY DATE_FORMAT('month', START_DATE);

This should group the data based on the month names and apply the count function.

Thanks for reading!!