-- 1. Select all columns from the Authors table
SELECT * FROM Authors;

-- 2. Select only specific column from the Authors table
SELECT AuthorID, AuthorLastName, AuthorFirstName FROM Authors;

-- 3. Filtering with WHERE Clause
SELECT * FROM Authors WHERE AuthorLastName = 'Smith

-- 4. Sorting with ORDER BY (Ascending)
SELECT * FROM Authors ORDER BY AuthorLastName ASC;

-- 5. Sorting with ORDER BY (Descending)
SELECT * FROM Authors ORDER BY AuthorLastName DESC;

-- 6. Limiting Rows with LIMIT
SELECT TOP 5 * FROM Authors;

-- 7. Combining WHERE and ORDER BY
SELECT * FROM Authors WHERE AuthorLastName LIKE 'S%' ORDER BY AuthorLastName;

-- 8. Aggregate Function with GROUP BY
SELECT COUNT(*), AuthorPhone FROM Authors GROUP BY AuthorPhone;

-- 9. Using Aggregate Function with WHERE
SELECT AVG(salary) from Employee where JobID = 1

-- 10. Select Distinct Values
SELECT DISTINCT AuthorPhone FROM Authors;

-- 11. Select with NULL Values
SELECT AuthorID, AuthorLastName, AuthorFirstName FROM Authors WHERE AuthorPhone IS NULL;