The same product twice in Microsoft Access

Today’s TechHelp tutorial from Access Learning Zone focuses on a scenario where you need to detect if a customer has purchased the same product twice – a situation that can often arise with memberships. When you manage memberships, it’s critical to ensure that your customers don’t accidentally sign up for the same membership more than once, leading to double billing. This topic stemmed from a question from Phoebe in Roswell, Georgia, who wanted a way to identify if a customer had accidentally signed up for the same membership more than once.

From my own experience, I have had similar problems with memberships such as Silver, Gold and Platinum. Sometimes it happens that a customer becomes a member on a certain day and forgets, only to sign up again later. Although my website is not programmed to prevent this, my database flags duplicate memberships, allowing me to quickly address any billing errors.

Today I’ll walk you through a method for setting up a routine that checks for duplicate purchases using Access queries. Although this is an expert-level task, you do not need to have any knowledge of VBA; instead, you need familiarity with aggregated searches. If you’re new to this, I recommend watching my introductory videos on summary searches and Access query criteria available on my website and YouTube channel.

In previous tutorials I showed how to avoid double entry in an order by using compound keys. However, the current method involves using an aggregate query, which provides flexibility for exceptions and generates a report with duplicates.

We’ll start by entering some data into a sample database. This free TechHelp template, available on my website, includes customers, orders, and products. Let’s illustrate this with an example: suppose a customer orders the same product twice, for example a ‘Silver Membership’. Using text fields or product IDs, we set up scenarios to test for duplicates.

We then design a query that brings together customer, order and order detail information. The goal is to list each customer along with their product purchases. By implementing sorting options, you can easily identify duplicate entries.

The main task is to group this data by customer and product, which allows us to count the number of occurrences of each product for each customer. This approach will highlight those who have purchased the same item more than once. Applying the appropriate criteria will refine the list so that only duplicates are shown.

After you customize the query to count events, you can delete individual entries. The search results will then only show customers who have purchased multiple quantities of the same product. This way you can manage exceptions while keeping an eye on potential double billing issues.

I encourage you to explore further Access lessons on my website, where I cover a range of topics from beginner to advanced, including queries, form design and database management.

For those who would like to follow this tutorial step by step, a complete video with in-depth instructions is available on my website. Live long and prosper, my friends.

For a full video tutorial on this topic, visit https://599cd.com/SameProductTwice?key=Dev.To