SQL Query Concepts and Syntax

The video tutorial introduces databases and SQL, explaining how databases store information in tables. It covers basic SQL commands like SELECT, FROM, and WHERE, and demonstrates how to use these commands to query data. The tutorial provides examples of SQL queries with conditions, including using boolean logic and wildcards for more advanced queries. The video concludes with a summary and encourages viewers to subscribe for more content.

What is the primary purpose of a database?

• To connect to the internet

• To display graphical data

• To store and organize large amounts of information

• To perform complex calculations

Which SQL command is used to retrieve data from a database?

• INSERT

• DELETE

• SELECT

• UPDATE

What does the WHERE clause in SQL do?

• It filters records based on a condition

• It specifies the table to query

• It sorts the results

• It groups the results

How would you write a query to find all cheeses priced over two pounds?

• SELECT * FROM cheese_table WHERE name = 'cheese'

• SELECT * FROM cheese_table WHERE price < 2

• SELECT name FROM cheese_table WHERE price > 2

• SELECT price FROM cheese_table WHERE name > 2

What result would you expect from the query: SELECT name, color FROM cheese_table WHERE strength = 2?

• All cheeses with strength not equal to 2

• All cheeses with strength less than 2

• All cheeses with strength 2 and their colors

• All cheeses with strength greater than 2

Which Boolean operator would you use to combine conditions in SQL?

• IN

• LIKE

• NOT

• AND

What is the result of the query: SELECT name, color FROM cheese_table WHERE strength > 1 AND color = 'yellow'?

• All cheeses with strength 1 and color yellow

• All cheeses with strength greater than 1 and color not yellow

• All cheeses with strength greater than 1 and color yellow

• All cheeses with strength less than 1 and color yellow

What does the asterisk (*) symbol represent in a SQL query?

• It selects a specific column

• It updates a column

• It selects all columns

• It deletes a column

How would you use a wildcard to find names starting with 'M'?

• SELECT * FROM table WHERE name LIKE '%M'

• SELECT * FROM table WHERE name = '%M%'

• SELECT * FROM table WHERE name = 'M%'

• SELECT * FROM table WHERE name LIKE 'M%'

What is the purpose of using wildcards in SQL?

• To delete records

• To create new tables

• To simplify queries by matching patterns

• To perform arithmetic operations