In Order to get difference between two dates in postgresql by days, weeks, months and years. We will be using abs() function along with date difference. Let’s see how to

- Get difference between two dates in Postgresql by days with an example.
- Get difference between two dates in Postgresql by weeks with an example.
- Get difference between two dates in Postgresql by months with an example.
- Get difference between two dates in Postgresql by years with an example.

The table we use is **student_detail1**

**Get difference between two dates in postgresql by days with an example:**

Difference between two dates in postgresql can be calculated by finding difference between two dates along with absolute function as shown below

select *,abs(birthday :: date - fin_date :: date) as diff_days from student_detail1;

So the resultant table will be

**Get difference between two dates in postgresql by weeks with an example:**

Difference between two dates in postgresql by weeks can be calculated by finding difference between two dates and dividing them by 7 along with absolute function as shown below

select *,abs(birthday :: date - fin_date :: date)/7 as diff_weeks from student_detail1;

So the resultant table will be

**Get difference between two dates in postgresql by months with an example:**

Difference between two dates in postgresql by months can be can be calculated by finding difference between two dates and dividing them by 365.25/12 along with absolute function as shown below

select *,round(abs(birthday :: date - fin_date :: date)/(365.25/12),2) as diff_months from student_detail1;

So the resultant table will be

**Get difference between two dates in postgresql by year with an example:**

Difference between two dates in R by year can be calculated by finding difference between two dates and dividing them by 365.25 along with absolute function as shown below

select *,round(abs(birthday :: date - fin_date :: date)/365.25,2) as diff_year from student_detail1;

So the resultant table will be