SQL Learning - Part 6 - Answers to the Exam Style Test

Of course I asked ChatGPT to provide me the answers to the exam style test i have listed as Checking your progress. Here you go:

Week 1: SQL Basics and Database Design

1. SQL stands for Structured Query Language.

2. A database is a structured collection of data.

3. A primary key is a unique identifier for a row in a table.

4. The SELECT statement is used to retrieve data from one or more tables.

5. A foreign key is a column or a set of columns that refer to the primary key of another table.

Week 2: DML and DDL

1. DDL stands for Data Definition Language and is used to define and manage the structure of a database.

2. DML stands for Data Manipulation Language and is used to manipulate the data stored in a database.

3. The CREATE TABLE statement is used to create a new table in a database.

4. The INSERT INTO statement is used to add new rows to a table.

5. The UPDATE statement is used to modify existing rows in a table.

Week 3: Joins and Aggregation

1. A join is used to combine data from two or more tables into a single result set.

2. The INNER JOIN keyword returns only the rows that have matching values in both tables.

3. The GROUP BY clause is used to group rows that have the same values into summary rows.

4. The COUNT function returns the number of rows that match a specified condition.

5. The MAX function returns the highest value in a column.

Week 4: Subqueries

1. A subquery is a query that is nested inside another query.

2. A correlated subquery is a subquery that depends on the outer query for its values.

3. The EXISTS operator is used to test for the existence of rows returned by a subquery.

4. The ANY operator is used to test if any of the values returned by a subquery satisfy a condition.

5. The ALL operator is used to test if all of the values returned by a subquery satisfy a condition.

Week 5: Views

1. A view is a virtual table based on the result set of a SELECT statement.

2. A view is used to simplify complex queries by abstracting the underlying data.

3. The CREATE VIEW statement is used to create a new view in a database.

4. A view can be used to restrict access to sensitive data in a database.

5. A view can be used to provide a customized view of data for different users or applications.