Mastering Basic SQL Concepts

What is the purpose of the SELECT statement in SQL?

• To update existing records in a database.

• To delete data from a database.

• To create new tables in a database.

• To retrieve data from a database.

How do you filter records in SQL using the WHERE clause?

• Use the SELECT clause to filter records in SQL.

• Use the WHERE clause to specify conditions for filtering records in SQL.

• The WHERE clause is used for sorting records in SQL.

• You cannot filter records in SQL using the WHERE clause.

What does the LIKE operator do in SQL?

• The LIKE operator is used to create new tables in a database.

• The LIKE operator is used to search for a specified pattern in a column.

• The LIKE operator is used to update existing records in a table.

• The LIKE operator is used to delete records from a table.

How can you combine multiple conditions in a SQL query using the AND operator?

• Use the NOT operator to combine multiple conditions in a query.

• Use the AND operator in the WHERE clause to combine conditions.

• Use the OR operator in the WHERE clause to combine conditions.

• Combine conditions by using the JOIN clause instead of WHERE.

Explain the functionality of the BETWEEN operator in SQL.

• The BETWEEN operator only filters results based on the upper endpoint.

• The BETWEEN operator is used to join two tables in SQL.

• The BETWEEN operator excludes the endpoints from the range.

• The BETWEEN operator filters results within a specified range, inclusive of the endpoints.

Write a SQL query to select all records where the age is between 18 and 25.

• SELECT * FROM table_name WHERE age > 18 AND age < 25;

• SELECT * FROM table_name WHERE age >= 18 OR age <= 25;

• SELECT * FROM table_name WHERE age IS NOT NULL;

• SELECT * FROM table_name WHERE age BETWEEN 18 AND 25;

How would you use the LIKE operator to find names starting with 'A'?

• SELECT name FROM table_name WHERE name LIKE 'A*';

• SELECT name FROM table_name WHERE name LIKE '%A';

• SELECT name FROM table_name WHERE name LIKE 'A_';

• SELECT name FROM table_name WHERE name LIKE 'A%';

What is the result of a query that uses both WHERE and AND clauses?

• The result is a complete set of records without any filtering.

• The result is a random selection of records from the database.

• The result is a filtered set of records that meet all specified conditions.

• The result is an unfiltered view of all records in the database.

Provide an example of a SQL query using the BETWEEN operator with dates.

• SELECT * FROM orders WHERE order_date > '2023-01-01' AND order_date < '2023-12-31';

• SELECT * FROM orders WHERE order_date NOT BETWEEN '2023-01-01' AND '2023-12-31';

• SELECT * FROM orders WHERE order_date = '2023-06-15';

• SELECT * FROM orders WHERE order_date BETWEEN '2023-01-01' AND '2023-12-31';

How can you combine the LIKE and AND operators in a single SQL query?

• SELECT * FROM table_name WHERE column1 = 'value1' AND column2 = 'value2';

• SELECT * FROM table_name WHERE column1 LIKE 'pattern1' AND column2 LIKE 'pattern2';

• SELECT * FROM table_name WHERE column1 LIKE 'pattern1' OR column2 LIKE 'pattern2';

• SELECT column1, column2 FROM table_name WHERE column1 LIKE 'pattern1' AND column2 = 'pattern2';