1.3.2 SQL selecting data (single table)

Question 1

what are the uses of SQL?

Answer 1

select data single table)
Select data (multiple tables)
Insert data
Delete records
Delete tables

Question 2

what does the SELECT command do?

Answer 2

Retrieves data from a database table.

Question 3

what does the FROM command do?

Answer 3

Specifies the tables to retrieve data from.

Question 4

what does the WHERE command do?

Answer 4

Filters the data based on specific condition.

Question 5

what does the LIKE command do?

Answer 5

Filter the data based on a specific pattern.
SELECT * FROM users
WHERE name LIKE ‘J%’;
(retrieves users whose names start with ‘J’)

Question 6

what does the AND command do?

Answer 6

combines multiple conditions in the where command.
SELECT * FROM users
WHERE age > 18 AND city = ‘New York’;
(retrieves users older than 18 and from New York)

Question 7

what does the OR command do?

Answer 7

retrieve data when at least one condition is met/true.
SELECT * FROM users
WHERE age < 18 OR city = ‘New York’;
(retrieves users younger than 18 or from New York)

Question 8

what does the command WILDCARD do?

Answer 8

‘’ and ‘%’ symbols are used for searching and matching data
‘’ used to select all columns in a table
‘%’ used as a wildcard character in the LIKE operator.