UPDATE statement in PostgreSQL

In this tutorial, We will be exploring how to update the data in an existing table.
Let's get started...

The UPDATE statement is used to modify the data in an existing table.

Syntax

UPDATE table_name
SET column1 = value1,
    column2 = value2,
    ...
WHERE condition;

In the above syntax, we can see that first we have specify the table name with the UPDATE keyword.
Second, we have to specify the columns that we want to update and their updated values after 'SET' keyword. Also note that those columns that do not appear in the 'SET' clause won't be modified.
Third, we have to write the conditions which rows to be updated in the table after the 'WHERE' clause.

If you want to return the row that is/are just modified use the following code in the end:

RETURNING *;

EXAMPLE
Let's look at the example and practice it.
Suppose we have the following table which shows all the courses and description:

1) Update one row from table
The following query will modify one row from the table that has id=2 and sets it published_date to 2020-07-01.

UPDATE courses
SET published_date = '2020-07-01'
WHERE course_id = 2
RETURNING *;

OUTPUT

Conclusion

In this article we learnt about the 'UPDATE' statement and it's example.