All 7 Dynamic SQL questions
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What is dynamic SQL, and why would you need to build and execute a SQL statement as a string rather than writing it directly? What is SQL injection, and how does it relate to writing dynamic SQL unsafely? How do you safely use sp_executesql to execute dynamic SQL with parameters, avoiding the risks of simple string concatenation? How would you build a dynamic SQL query where the table or column names themselves need to change based on input, since parameters cannot be used for object names? How would you build a dynamic SQL statement inside a stored procedure that constructs a flexible search query based on several optional filter parameters? What are the performance tradeoffs of using dynamic SQL compared to static, precompiled SQL statements?
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SQL Server › Dynamic SQL

How do you debug a dynamic SQL statement when it fails or does not produce the expected results?

Intermediate

Answer

A helpful technique is to print or select the final generated SQL string before actually executing it, letting you visually inspect the exact statement that would run and catch any syntax errors or unexpected values, which is often much easier than trying to debug the error message that comes back from executing a broken dynamic query directly.
DECLARE @SQL NVARCHAR(MAX) = N'SELECT * FROM Orders WHERE CustomerId = @Id';
PRINT @SQL; -- inspect before executing
EXEC sp_executesql @SQL, N'@Id INT', @Id = 123;
Real-world example A developer troubleshooting a dynamic SQL query that keeps failing adds a PRINT statement to see the exact generated SQL text, quickly spotting a missing space that was causing a syntax error.

Common follow-ups: What other debugging techniques help when working with complex dynamic SQL?;Should PRINT statements be removed before deploying dynamic SQL to production?

Error Handling with TRY CATCH;Stored Procedures & Functions
All 7 Dynamic SQL questions