Contents
What is customer deduplication?
Customer deduplication is the process of finding and merging records in a database that pertain to the same person. In modern companies, the collection of customer information is done in various ways. Most often, data is entered by managers into CRM systems, or customers fill out forms themselves when registering on a website. If data comes in different formats, it can lead to the creation of "dirty" data — incomplete, erroneous, and duplicate records.
Duplicates are repeated entries for the same customer. For example, if a user forgets their password and registers again, the company may think it has two different customers when in reality it is the same person. The presence of duplicates distorts the actual number of customers and can lead to irrational business decisions. To avoid such problems, it is necessary to regularly conduct deduplication of the customer database.
How do duplicates enter the database?
Duplicates can appear in the database for various reasons, most often accidentally due to carelessness or software errors. Here are some common scenarios when duplicates are created:
- Creation of duplicates by customers: Sometimes users create multiple accounts to take advantage of bonuses or discounts for new customers.
- Sales manager errors: If information about a customer already exists in the database but was entered incorrectly, a manager may create a new record without finding the necessary one.
- Merging databases: When combining different databases, duplicates may arise if the format of records differs, for example, one database records the date as dd.mm.yyyy, while another as mm.dd.yyyy.
- Full and partial duplicates: Full duplicates have identical data, while partial duplicates match only in certain fields, such as full name and email address.
The dangers of duplicates in the customer database
The existence of duplicates in the customer database can cause serious problems, such as:
- Increased data storage costs: Every message sent to a customer takes up space on the server, and duplicates only increase these costs.
- Increased advertising costs: The budget for marketing campaigns may depend on the size of the customer base, and duplicates make services more expensive without real returns.
- Worsened company reputation: Multiple sends of the same messages annoy customers and can lead to unsubscribes or marking messages as "SPAM".
- Poor quality of business decisions: Duplicates distort the data on which decisions are made. For example, analysis may show that customers are not making repeat purchases, while in reality, these are the same people using different accounts.
Methods of data deduplication
For effective data deduplication, several methods can be used:
- Using spreadsheet software: For example, Excel allows the use of filters to find and remove duplicates. This method is suitable for small databases.
- SQL queries: SQL allows for managing databases and conducting deduplication through commands that process data and identify potential duplicates.
- Third-party services: There are special programs and services that help automate the deduplication process, such as Datablist, OpenRefine, and others. Paid versions offer more complex algorithms and support.
Each of these methods has its advantages and disadvantages, so the choice of the appropriate solution depends on the specific needs of the company and the volume of data.