SQL for Java Devs · interview question
Which JDBC feature allows mapping SQL NULL values to Java null when retrieving column values?
Multiple choiceHardchapter-8-curatedpremiumsql-for-java-devsresultsets-and-mapping
Answer and explanation
Correct answer
C. Using rs.wasNull() after each get method
Why
After retrieving a column value, rs.wasNull() can be called to check if the result was SQL NULL, allowing you to set the Java value to null if needed. This ensures accurate null handling.
Test yourself on SQL for Java Devs
A free test with instant, explained results. No account needed.
More SQL for Java Devs questions
- How can JDBC transactions help maintain data integrity during an e-commerce checkout process?
- What would be the effect of not closing a PreparedStatement in a Java application?
- In JDBC, how do you ensure that SQL injection is prevented when executing a query that searches for a user by email?
- Why do teams use SQL JOINs to fetch relational data in a single query in production code?
- What should a repository method mainly encapsulate?
- How can you prevent the N+1 query problem when retrieving a list of orders with their customer details?