A software tool that diagrammatically illustrates SQL Select queries by parsing them.
Revj, short for Reverse Snowflake Joins, is an invaluable tool for comprehending and documenting SQL queries. It's especially useful for maintaining large queries written by someone else. These "big SQL" queries can involve up to 20 tables, each linked via multiple fields. The tool displays parts of a query directly in the diagram, including elements like age=30, GROUP BY (year), and HAVING MIN(age) > 18.
Creating correct queries for complex joins is a challenging task since many tools fail to generate effective SQL. As such, even manually crafted queries can be prone to errors, such as forgetting to remove a table when it is no longer required for filtering or grouping by a field within that table. Needless to say, disconnected tables can result in a cartesian product, and while there can be valid reasons for using them, it's not a typical scenario. Similarly, loops are usually undesirable.
It's important to note that Revj isn't an EXPLAIN tool. If a cartezian join is mistakenly written, even the best indexes won't rectify the issue. Additionally, it's not a query execution tool. Although there are numerous such tools available with features like drag-and-drop and predictive typing, and everyone likely has their favorite already. But if you're looking for a powerful tool specific to understanding and documenting SQL queries with complex joins, look no further than Revj.
Creating correct queries for complex joins is a challenging task since many tools fail to generate effective SQL. As such, even manually crafted queries can be prone to errors, such as forgetting to remove a table when it is no longer required for filtering or grouping by a field within that table. Needless to say, disconnected tables can result in a cartesian product, and while there can be valid reasons for using them, it's not a typical scenario. Similarly, loops are usually undesirable.
It's important to note that Revj isn't an EXPLAIN tool. If a cartezian join is mistakenly written, even the best indexes won't rectify the issue. Additionally, it's not a query execution tool. Although there are numerous such tools available with features like drag-and-drop and predictive typing, and everyone likely has their favorite already. But if you're looking for a powerful tool specific to understanding and documenting SQL queries with complex joins, look no further than Revj.
What's New
Version 0.35: N/A