Title: SQL Starter Pack: Navigating Data Analytics with SQL
Description:
Structured Query Language (SQL) is a cornerstone for data analytics, allowing you to interact with and extract insights from databases. In this beginner’s workout, you’ll embark on your SQL journey, mastering the fundamental commands and concepts essential for data analytics.
Scenario:
You’re an analyst at a retail company, and you’ve been given access to their database. Your task is to extract basic sales and customer data to understand sales performance. How will you harness SQL to retrieve and analyze this data?
Objectives:
By the end of this workout, you should be able to:
Understand basic SQL syntax and structure.
Use SQL to retrieve data from tables using the SELECT statement.
Filter and sort data using WHERE and ORDER BY clauses.
Interactive Task:
Given your beginner’s understanding of SQL, answer the following:
How would you retrieve all columns from a table named sales_data?
Your Approach: ________________________
If you want to retrieve only the product_name and sales_amount columns from the sales_data table, how would you structure your query?
Your Approach: ________________________
You want to get a list of customers from the customers table who joined after January 1, 2022, and sort them by their joining date in descending order. What would your SQL query look like?
Your Answer: ________________________
Questions:
In SQL, which keyword is used to filter the results of a query based on specific criteria?
i) FILTER
ii) SORT
iii) WHERE
iv) FIND
If you want to sort the results of an SQL query in ascending order based on a specific column, which keyword would you use?
i) SORT
ii) ORDER BY
iii) ARRANGE
iv) ORGANIZE
Duration: 20 minutes
Difficulty: Beginner
Period:
This workout is released on Tuesday, October 10, 2023, and will end on Friday, October 20, 2023. But you can always come back to any of the workouts and solve them.
In SQL, which keyword is used to filter the results of a query based on specific criteria?
Answer:
iii) WHERE
If you want to sort the results of an SQL query in ascending order based on a specific column, which keyword would you use?
Answer:
ii) ORDER BY
Interactive Task:
How would you retrieve all columns from a table named sales_data ?
answer:
To retrieve all columns from a table named “sales_data” in SQL, you would use the SELECT statement without specifying any column names. Here’s the SQL query to achieve this:
SELECT *
FROM sales_data;
The * is a wildcard character that represents all columns in the table. When you use SELECT *, it retrieves all the columns from the specified table, making it a simple way to select all data from that table.
If you want to retrieve only the product_name and sales_amount columns from the sales_data table, how would you structure your query?
Answer:
To retrieve only the “product_name” and “sales_amount” columns from the “sales_data” table in SQL, you would structure your query as follows:
SELECT product_name, sales_amount
FROM sales_data;
This SQL query explicitly specifies the columns you want to retrieve (product_name and sales_amount) and the table you are selecting from (sales_data). It will return only these two columns from the “sales_data” table in the query result.
You want to get a list of customers from the customers table who joined after January 1, 2022, and sort them by their joining date in descending order. What would your SQL query look like?
Answer:
To get a list of customers from the “customers” table who joined after January 1, 2022, and sort them by their joining date in descending order, your SQL query would look like this:
SELECT *
FROM customers
WHERE join_date > '2022-01-01'
ORDER BY join_date DESC;
In this query:
We use the SELECT statement to retrieve all columns from the “customers” table.
The WHERE clause is used to filter the results, selecting only rows where the “join_date” is greater than ‘2022-01-01’.
The ORDER BY clause is used to sort the results by the “join_date” column in descending order (latest dates first).
How would you retrieve all columns from a table named sales_data ?
SELECT *
FROM sales_data;
If you want to retrieve only the product_name and sales_amount columns from the sales_data table, how would you structure your query?
SELECT product_name, sales_amount
FROM sales_data;
You want to get a list of customers from the customers table who joined after January 1, 2022, and sort them by their joining date in descending order. What would your SQL query look like?
SELECT *
FROM customers_data
WHERE customers_join_date > ‘2022-01-01’
ORDER BY customers_join_date desc;
Questions
In SQL, which keyword is used to filter the results of a query based on specific criteria?
iii) WHERE
If you want to sort the results of an SQL query in ascending order based on a specific column, which keyword would you use?