PostgreSQL SQL for Beginners

PostgreSQL Example – How to Apply Operation To Column

By on Friday, June 4, 2021

Apply Operation To Column

Create Table Of Adventurers

- Create table called adventurers
CREATE TABLE adventurers (
    - string variable
    name varchar(255),
    - integer variable
    age int,
    - string variable
    race varchar(255)
)

Insert Rows

- Insert into the table adventurers
INSERT INTO adventurers (name, age, race)
VALUES ('Fjoak Doom-Wife', 28, 'Human'),
       ('Alooneric Cortte', 29, 'Elf'),
       ('Piperel Ramsay', 35, 'Elf'),
       ('Casimir Yardley', 14, 'Elf')

Apply Operation To Column

- Update the age column, multiplying all age values by 10
UPDATE adventurers SET age = age * 10

Apply Operation To Column With Conditions

- Update the name column where the race column is 'Elf'
UPDATE adventurers SET name = 'Some Elf'
WHERE race = 'Elf'

View Table

- Retrieve data
SELECT * FROM adventurers
name age race
Fjoak Doom-Wife 280 Human
Some Elf 290 Elf
Some Elf 350 Elf
Some Elf 140 Elf

 

 

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