How to Pivot Two Rows into Columns Using BigQuery скачать в хорошем качестве

How to Pivot Two Rows into Columns Using BigQuery

Discover how to effectively `pivot data` in Google BigQuery to transform rows into columns for better analysis and presentation. --- This video is based on the question https://stackoverflow.com/q/69274216/ asked by the user '16143' ( https://stackoverflow.com/u/11747938/ ) and on the answer https://stackoverflow.com/a/69274246/ provided by the user 'Gordon Linoff' ( https://stackoverflow.com/u/1144035/ ) 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: Pivot 2 rows bigquery 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 Pivot Two Rows into Columns Using BigQuery Pivoting data can be a critical task in data analysis, especially when using platforms like Google BigQuery. It allows you to transform data in a way that makes it easier to analyze and visualize. In this post, we’ll tackle a common problem that many users encounter: pivoting two rows into columns. Let’s walk through the steps to achieve this effectively. The Problem Imagine you have a dataset that looks like this: [[See Video to Reveal this Text or Code Snippet]] From this dataset, you want to transform it into a table where col_2 values become the column headers. The resulting data should look like this: [[See Video to Reveal this Text or Code Snippet]] The challenge is to reformat the data correctly, with the correct aggregations, based on the col_2 values. The Solution: Using Conditional Aggregation To pivot your data as desired, you can utilize conditional aggregation instead of the PIVOT function. Here's a detailed breakdown of how to implement this solution. Step 1: Understand the Structure Before we pivot, let's analyze our data structure: ID: This is our primary key. col_1: This column remains the same. col_2: This will become our new column headings. col_3 and col_4: These columns will hold values that correspond to col_2's entries. Step 2: Write the Query Here’s the SQL code to achieve the desired pivot: [[See Video to Reveal this Text or Code Snippet]] Explanation of the Query Components MAX and CASE: We are using a combination of MAX and CASE statements to extract values based on the conditions defined for col_2. This is the core logic behind pivoting in SQL. GROUP BY: The GROUP BY clause is essential here as it aggregates the results based on the unique IDs, ensuring that we collapse the rows into a single row for each ID. Step 3: Run the Query Once you execute the query, it will transform your data from the original structure into the pivoted structure we aimed for. You can view the results and confirm that they match your expectations. Conclusion Pivoting rows into columns in BigQuery can enhance your data analysis by making the datasets more structured and comprehensible. By using conditional aggregation instead of the PIVOT function, you can effectively achieve the desired output. In this post, we walked through the problem of transforming rows into columns, provided a clear solution using SQL, and explained the logic behind it. Explore this approach, and you'll find it's a powerful tool in your data manipulation toolkit!