SQL Query and Data Manipulation Concepts

This video tutorial by Mosh Hamedani provides a comprehensive introduction to SQL, covering installation, database creation, and basic to advanced SQL queries. It explains the use of various SQL clauses, operators, and joins, and demonstrates data manipulation techniques such as inserting, updating, and deleting records. The course concludes with additional resources for further learning.

What is the primary purpose of SQL?

• To write operating systems

• To manage and manipulate databases

• To create web pages

• To design graphics

Which of the following is a correct use of the SELECT statement?

• FROM table_name SELECT *;

• SELECT table_name FROM *;

• SELECT * FROM table_name;

• SELECT table_name * FROM;

How can you filter data to show only customers from Virginia using the WHERE clause?

• WHERE state = 'Virginia';

• WHERE state LIKE 'Virginia';

• WHERE state IN 'Virginia';

• WHERE state BETWEEN 'Virginia';

Which operator would you use to find customers whose last names start with 'B'?

• WHERE last_name BETWEEN 'B%';

• WHERE last_name IN 'B%';

• WHERE last_name LIKE 'B%';

• WHERE last_name = 'B%';

Which special character in regular expressions is used to indicate the start of a string?

• Dollar sign ($)

• Square brackets []

• Pipe (|)

• Caret (^)

What is the purpose of using an alias in SQL queries?

• To simplify query syntax and avoid repetition

• To rename a table permanently

• To delete a table

• To create a new table

In SQL, what does the LIMIT clause do?

• It sorts the data in ascending order

• It deletes records from a table

• It restricts the number of records returned by a query

• It joins two tables

What is the main advantage of using the USING clause in SQL joins?

• It allows for joining tables with different column names.

• It automatically optimizes the query for better performance.

• It simplifies the join condition when column names are the same in both tables.

• It allows for joining tables without specifying any conditions.

Which type of join would you use to combine every record from one table with every record from another table?

• Natural Join

• Cross Join

• Left Join

• Inner Join

When inserting data into a table with an auto-increment column, what is the recommended approach?

• Use the DEFAULT keyword to let the database handle it.

• Use a subquery to determine the next value.

• Manually specify the value for the auto-increment column.

• Leave the column out of the insert statement entirely.