SQL: Data Manipulation

Add data to a table

INSERT

: Adds a single row to the table

INSERT INTO MyTable (col1, col2)
VALUES ('value1', 'value2');

INSERT INTO people (first_name, last_name)
VALUES
('George', 'White'),
('Jenn', 'Smith'),
('Carol', NULL);

Modify data in a table

UPDATE

: Updates table data

UPDATE MyTable
SET col1 = 56
WHERE col2 = 'something';

• WHERE clause: it targets only the correct record.
• We need to be as specific as possible with our statement.

UPDATE people
SET last_name = 'Morrison'
WHERE id_number = 175;

Remove data from a table

DELETE

: Removes rows from the table

DELETE FROM MyTable
WHERE col1 = 'something';

DELETE FROM people
WHERE id_number = 1001;

DELETE FROM people
WHERE quiz_points IS NULL;