PostgreSQL UPDATE

The UPDATE Statement

The UPDATE statement is used to modify the value(s) in existing records in a table.

Example

Set the color of the Volvo to ‘red’:

UPDATE cars
SET color = 'red'
WHERE brand = 'Volvo';

Result

UPDATE 1

Which means that 1 row was affected by the UPDATE statement.

Note: Be careful with the WHERE clause, in the example above ALL rows where brand = ‘Volvo’ gets updated.

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Display Table

To check the result we can display the table with this SQL statement:

Example

SELECT * FROM cars;

Run Example »

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Warning! Remember WHERE

Be careful when updating records. If you omit the WHERE clause, ALL records will be updated!

Example

Without the WHERE clause, ALL records will be updated:

UPDATE cars
SET color = 'red';

Result

UPDATE 4

Which means that all 4 row was affected by the UPDATE statement.

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Display Table

To check the result we can display the table with this SQL statement:

Example

SELECT * FROM cars;

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Update Multiple Columns

To update more than one column, separate the name/value pairs with a comma ,:

Example

Update color and year for the Toyota:

UPDATE cars
SET color = 'white', year = 1970
WHERE brand = 'Toyota';

Result

UPDATE 1

Which means that 1 row was affected by the UPDATE statement.

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Display Table

To check the result we can display the table with this SQL statement:

Example

SELECT * FROM cars;

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PostgreSQL Exercises

Test Yourself With Exercises

Exercise:

Write the correct SQL statement to update the value of the model column to ‘Bronco’ for any record where the brand is ‘Ford’: cars model = ‘Bronco’ WHERE brand = ‘Ford’;