How to Group Different Rows in One Column Using SQL

Описание: Learn how to effectively group different rows in a single SQL column for summarizing budget categories and enhancing your database reporting.
---
This video is based on the question https://stackoverflow.com/q/67715975/ asked by the user 'Xerxes' ( https://stackoverflow.com/u/16044580/ ) and on the answer https://stackoverflow.com/a/67716095/ provided by the user 'Caius Jard' ( https://stackoverflow.com/u/1410664/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: How to group different rows in one column?

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Group Different Rows in One Column Using SQL

In the world of databases, grouping rows is a fundamental task that helps in summarizing and analyzing data efficiently. If you're managing a project that requires you to summarize various budget categories into one column, this post will guide you step-by-step through the process of achieving this using SQL.

The Problem at Hand

You may have a database with financial data that lists various expense categories. For example, let's consider the following categories you've recorded in your table:

Water

Electricity

Gas

Rentals

Hospital Fees

Medicine

Personal Care

Fitness

Your goal is to categorize and sum these expenditures into broader groups. Specifically, you want to create two main categories:

Utility Bills - which includes Water, Electricity, Gas, and Rentals.

Healthcare - which encompasses Hospital Fees, Medicine, Personal Care, and Fitness.

Now, the question is: How do you write an SQL query that allows you to select the sums for these categories efficiently?

Solution Overview

To group these different rows in one column and summarize your expenses, you'll need to organize your data in a structured way. There are a few steps involved in constructing the right SQL statements to achieve your goal.

Step 1: Organizing Your Data

Mapping Categories: You need to set up your data to reflect the grouping of categories. This can be accomplished in two ways:

Single Table Approach: Include a CategoryGroup in your main bills table.

Separate Mapping Table: Create a separate table that correlates categories with groups.

Example Structures:

Single Table Example:

[[See Video to Reveal this Text or Code Snippet]]

Separate Table Example:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Writing the SQL Query

Once your data is structured correctly, you’ll use the SQL GROUP BY clause to summarize the expenses. Depending on how you've organized your data, you will write one of these queries:

If using the Single Table Approach:

[[See Video to Reveal this Text or Code Snippet]]

If using the Separate Mapping Table:

[[See Video to Reveal this Text or Code Snippet]]

Step 3: Understanding the Results

By executing either of the above queries, you'll retrieve a summary result that gives you the total amounts for your defined groups, which might look something like this:

[[See Video to Reveal this Text or Code Snippet]]

In this format, you can clearly see how much you've spent on utility bills versus healthcare costs, providing a more organized view of your expenses.

Conclusion

Grouping rows in SQL can significantly enhance your data reporting capabilities, especially when managing various categories like budgets. By organizing your data correctly and understanding how to use GROUP BY, you can efficiently analyze and present your financial figures.

Feel free to apply these methods to your own SQL projects, and watch as your data becomes clearer and more actionable! If you have any questions or need further assistance, don't hesitate to reach out.