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How to Sort Data by Rows in MySQL

Discover the process of sorting data by rows in MySQL, including using a Common Table Expression for efficient and organized results. --- This video is based on the question https://stackoverflow.com/q/65229536/ asked by the user 'Anusorn Kongthong' ( https://stackoverflow.com/u/10613101/ ) and on the answer https://stackoverflow.com/a/65229831/ provided by the user 'Akina' ( https://stackoverflow.com/u/10138734/ ) 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 can i sort data by rows? [MYSQL] 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 Sort Data by Rows in MySQL: A Step-by-Step Guide Sorting data is an essential part of database management, especially when you want to retrieve information in a particular order. In MySQL, when you have data organized in rows, you may encounter situations where you need to sort these rows based on a specific criterion — such as grouping by the most frequent values in a column. Today, we'll explore how to achieve this through a practical example. Problem Overview Imagine you have a database with a table that includes multiple entries, and you want to sort these entries by rows that have the same highest count of values. For example, in our table, we want to prioritize rows with the same create_by value, specifically those that appear most frequently. This task can seem complex, but with the right MySQL commands, it becomes quite manageable. Sample Data Let's take a look at a sample table structure we are working with: idtitlecreate_by1aaa22bbb13ccc34ddd25eee26fff3Desired Output After sorting, you want to see the rows organized such that those with the same create_by value and that occur most often are grouped together. The expected output should look like this: idtitlecreate_by1aaa24ddd25eee23ccc36fff32bbb1Solution Breakdown We can achieve the desired sorting using a Common Table Expression (CTE) in MySQL. This feature allows us to create a temporary result set that we can refer to within a SELECT, INSERT, UPDATE, or DELETE. Here’s a breakdown of how to formulate our query. Step 1: Using CTE to Count Rows To start, we create a CTE that counts occurrences of each create_by value. Here's the SQL code for that: [[See Video to Reveal this Text or Code Snippet]] In this step: We select the id, title, and create_by from the source table (src_table). We use the COUNT function along with OVER (PARTITION BY create_by) to count how many times each create_by value appears, labeling this count as cnt. Step 2: Selecting from the CTE Next, we want to extract data from our CTE and sort it accordingly. Here’s the second part of the query: [[See Video to Reveal this Text or Code Snippet]] In this step: We select id, title, and create_by from the results of the CTE. We ORDER BY cnt DESC will organize the rows starting from the highest occurrences to the lowest. The id is included in case of ties to maintain a consistent order among entries having the same cnt value. Final Thoughts Sorting data in MySQL by rows based on the most frequent values can directly enhance the relevance and accessibility of your data. The approach we walked through, utilizing a CTE, allows for efficient handling of the query and results in a well-structured output. Feel free to adapt this sorting method for other datasets to extract valuable insights or organize information effectively! If you have further questions or need assistance, don’t hesitate to reach out. Happy coding!