У нас вы можете посмотреть бесплатно How to Generate a Hash Value for All Columns in a SQL Table или скачать в максимальном доступном качестве, видео которое было загружено на ютуб. Для загрузки выберите вариант из формы ниже:
Если кнопки скачивания не
загрузились
НАЖМИТЕ ЗДЕСЬ или обновите страницу
Если возникают проблемы со скачиванием видео, пожалуйста напишите в поддержку по адресу внизу
страницы.
Спасибо за использование сервиса ClipSaver.ru
Discover a straightforward way to generate a hash value for every record in your SQL table, making data comparison and integrity checks easier. --- This video is based on the question https://stackoverflow.com/q/77660916/ asked by the user 'hashdif' ( https://stackoverflow.com/u/23097186/ ) and on the answer https://stackoverflow.com/a/77661846/ provided by the user 'John Cappelletti' ( https://stackoverflow.com/u/1570000/ ) 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: Is it possible to generate a hash value for all columns in a table? 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 Generate a Hash Value for All Columns in a SQL Table When working with databases, ensuring data integrity and consistency can become a challenge, especially when transferring records between SQL databases. One effective method to verify the accuracy of your records is by generating a unique hash value for each row in your table. This post will guide you through the process of creating a hash value for all columns in a SQL table and inserting it into a target table. The Problem Statement You have two SQL tables: a source table from which you are fetching data and a target table that will receive this data along with an additional column for the hash value (hash_dif). The struggle lies in how to generate a hash value based on all the columns in your source table and insert this hash value together with the data in the target table. To achieve this, you want to: Select all records from your source table. Create a hash value for those records. Insert both the selected records and the generated hash value into your target table. The Solution Explained To generate a hash value and select all records from your source table simultaneously, you can use SQL's built-in functions. Below, we will break down the process in simple steps: Step 1: Selecting Records from the Source Table You will begin by selecting all records from your source table using: [[See Video to Reveal this Text or Code Snippet]] Step 2: Generating a Hash Value You can generate a hash using the following SQL command: [[See Video to Reveal this Text or Code Snippet]] This command generates a hash value for all the records by converting the selected data into a varbinary(max) format and applying the HashBytes function with the MD5 algorithm. Step 3: Combining Selection and Hash Generation However, executing the selection and hash generation simultaneously can pose a challenge. Instead of specifying each column, you can employ the CROSS APPLY function to dynamically create the hash value like this: [[See Video to Reveal this Text or Code Snippet]] Key Notes: CROSS APPLY: This allows you to join each row of your source table with the related hash value generated. It effectively combines the two operations in a single query. SHA2_512: Using SHA2_512 is generally recommended over MD5 for better security and less likelihood of hash collisions. FOR JSON PATH: This method helps in converting the selected rows into JSON format, which is then hashed. Conclusion Generating a hash value for every record in your SQL table allows you to easily verify the integrity of your data during migrations or comparisons. By following the steps outlined above, you can effectively implement this in your SQL queries, ensuring that your target table not only receives data but also a unique identifier for each record through hash values. With these methods at your disposal, you now have the tools to efficiently handle data integrity across your SQL databases.