SQL for Java Devs · interview question
Which JDBC feature can be used to map SQL NULL values to Java null?
Multiple choiceMediumchapter-8-curatedpremiumsql-for-java-devsresultsets-and-mapping
Answer and explanation
Correct answer
B. Rs.wasNull()
Why
The rs.wasNull() method checks if the last column read had a NULL value, allowing developers to map SQL NULLs to Java nulls accurately.
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?