What are the best practices for testing queries with user input?

Use parameterized queries to avoid SQL Injections and validations for user inputs. * Use naming conventions for parameters and variables to distinguish which one is parameter or variable, e.g. "v for Variables, p for Parameters" (Don't change the parameter values of user input by mistaken)

To ensure safe and efficient SQL queries with user input: 1. Use Prepared Statements: They prevent SQL injection and are more efficient for repeated queries. 2. Validate Input: Check for correct data type, length, and format before using in a query. 3. Limit User Input: Restrict the scope of what users can input, like using dropdowns or predefined options. 4. Test with Different Inputs: Include edge cases, unusual characters, and different data types to ensure robustness. 5. Review Query Performance: Analyze and optimize queries for different inputs to maintain performance. 6. Use Transaction Management: For complex queries, ensure data integrity with transactions, rolling back in case of errors.

Parameterized queries are a cornerstone of secure and efficient database interaction. By using them, developers can ensure that the data is strictly interpreted as input, eliminating the risk of SQL injection attacks, which are a common vulnerability in web applications. Furthermore, parameterized queries contribute to performance gains, as they allow the database engine to cache the execution plan for the query, making subsequent executions with different parameters faster. we always advocate for their use, as they align with the principles of secure, scalable, and maintainable software development.

acá hay que hacer gran hincapié en detectar que traigan malas prácticas,y formarlos en detectar, esas falencias para que tengan buenas prácticas, ya que filtrar caracteres implica que dependiendo de cómo lo hagas implica consumo de tiempo. dejarían por un tiempo colgado eliminando caracteres. hay datos de entrada que no deberían ser considerados como datos. un precio, debería ser traído de la base no del formulario. así como por ejemplo cupones de descuento, id y consulta de la base. te imaginas que un cliente angular no haga esto por back y si en front. le pasa el precio al gateway de pago, y bueno se imaginaran , capas para ciertas organizaciones suene obvio.pero no todo programador , he visto cada cosa.

Dummy data are always good way to understand missing cases of queries. * There is always a need for dummy data where different situations can be simulated. Don't focus on cases of your query, think different cases to fail your business logic. * Don't forget to test your data quality and structure(We cannot always have the most ideal data.)

* Learn how to read execution plan of RDBMS you work on. (It is most effective way to understand your query structure and analyze performans issues) * Print statement is another useful way. (You can use it step-by-step between your code blocks and see your inputs and outputs) * Raiserror is another statement to catch unwanted cases of the business logic. (You can use it to catch fail situations) * Most GUIs have built-in debug tools. (You can use GUIs to debug your code with break points)

Using logging and monitoring are best ways to find performance and logical issues. * Build a custom logging mechanism to log for needs and specific parts of the queries, e.g. "Log how many different values come for parameters and analyze filtered index needs" * Use Query Store or equivalent to catch all performance issues and missing indexes

I always log the steps and results of the custom mechanisms such us maintenance automation and table partitioning automation I created so that I can analyze them in the future and see if they were working correctly. I recommend this to all of you.