Prompt
WITH Revenue AS (
SELECT SUM(total_amount) AS TotalRevenue, COUNT(order_id) AS TotalPurchases
FROM sales
),
UniqueCustomers AS (
SELECT COUNT(DISTINCT customer_id) AS UniqueCustomers
FROM sales
)
SELECT
(SELECT TotalRevenue FROM Revenue) / (SELECT TotalPurchases FROM Revenue) AS AveragePurchaseValue,
(SELECT TotalPurchases FROM Revenue) / (SELECT UniqueCustomers FROM UniqueCustomers) AS AveragePurchaseFrequencyRate
Answer
This code snippet is written in SQL, a language typically used to manage and manipulate databases. It calculates two marketing metrics: the Average Purchase Value and the Average Purchase Frequency Rate. These are calculated from a Sales
database table and the results are returned in the final SELECT
statement.
Code Analysis
Common Table Expressions (CTEs) The code starts with two CTEs (Common Table Expressions),
Revenue
andUniqueCustomers
. CTEs are temporary views created and exist only during the execution of the query. They improve the readability of complex queries.The
Revenue
CTE calculates the total revenue and the total number of purchases.SUM(total_amount)
totals all the purchase amounts to provide revenue andCOUNT(order_id)
counts all the sale transactions to provide the number of purchases.The
UniqueCustomers
CTE calculates the number of unique customers by applying theCOUNT(DISTINCT customer_id)
operation.DISTINCT
ensures that only unique occurrences ofcustomer_id
are counted.
Final SELECT Statement The final SELECT statement calculates and presents the two marketing metrics:
AveragePurchaseValue
is calculated by dividing the total revenue by the total number of purchases (from theRevenue
CTE).AveragePurchaseFrequencyRate
is calculated by dividing the total number of purchases by the number of unique customers (One fromRevenue
CTE and one fromUniqueCustomers
CTE).
Key Concepts
CTE (Common Table Expression)
: This is a temporary view created at runtime which ceases to exist after execution. They help simplify complex queries.COUNT() and SUM() Functions
:COUNT()
is a SQL aggregate function for counting the number of rows in a database table whileSUM()
adds up the numeric values in a set of data.SELECT Statement
: This is a SQL command used to select data from a database and present it in a structured way.Distinct Keyword
:Distinct
is used to remove duplicates from a result set.
For instance, the code can be modified to calculate different metrics such as Average Order Amount
and Total Sales Per Customer
where Average Order Amount
can be calculated by dividing TotalSales
by TotalOrders
and Total Sales Per Customer
by dividing TotalSales
by UniqueCustomers
.
Description
This SQL snippet calculates Average Purchase Value and Average Purchase Frequency Rate from a 'Sales' table using Common Table Expressions (CTEs) for revenue and unique customers. It highlights the usage of CTEs, COUNT(), SUM(), SELECT statement, and Distinct keyword for marketing data analysis.