How to add seconds to a timestamp to get an ending timestamp?

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How to add seconds to a timestamp to get an ending timestamp?

Assume you have have 2 values:

starting timestamp

duration (seconds)

How do you determine the ending time? 

There are a number of ways this can be done and here are two:

The first one is to use an interval as your second column.

CREATE TABLE time_test (one TIMESTAMP, duration INTERVAL);
INSERT INTO time_test VALUES (now(), '10 seconds');
SELECT one, one + duration AS duration FROM time_test;

            one             | duration          

----------------------------+----------------------------

 2020-04-08 10:03:34.806522 | 2020-04-08 10:03:44.806522

The second option is to use the function make_interval():

CREATE TABLE time_test_2(one TIMESTAMP, duration INTEGER);
INSERT INTO time_test_2 VALUES(now(), 10);
SELECT one, one + make_interval(secs => duration) AS duration FROM time_test_2;

            one             | duration          

----------------------------+----------------------------

 2020-04-09 13:51:53.703337 | 2020-04-09 13:52:03.703337

This is just the first of a series of simple tips that we will be delivering to make your life easier with Postgres!