How to Count Unique Email Addresses in a Database Table?

Finding Unique Email Counts in a Database Table

Counting the number of unique values in a database table is a common task, especially when analyzing data for insights. Let's consider the case where you have a table with three columns: orderNumber, name, and email. Your goal is to determine the count of unique email addresses in the table.

Initially, you attempted to use SELECT count(email) FROM orders, but this query returned the total email count, which includes duplicate values. To count unique emails, it's essential to add the DISTINCT keyword to your query.

However, simply using SELECT DISTINCT count(email) FROM orders may not be sufficient. To obtain the desired count, you need to use COUNT(DISTINCT(email)). This syntax ensures that the DISTINCT keyword is applied to the email column before counting.

By executing the query SELECT count( DISTINCT(email) ) FROM orders, you will correctly determine the count of unique email addresses in the orders table.

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