DB - LISTAGG() function | Aggregate fuction

Sometimes we need to aggregate data from a number of rows into a single row and associate the result row with a specific value.

For example, following query returns a comma separated list of employees for each job title.

Table:

Employees:

Employee_Id

First_name

Last_name

Email

Phone

Hire_date

Manager_id

Job_title

Query:

Select 

Job_title,

LISTAGG(

First_name, ',',) within group( order by first_name) as employees

From employees

Group by job_title

Order by

Job_title;