What is the best practice for handling SQL exceptions in a multi-tier application?
- Catch and log the exception at the point of occurrence
- Convert the SQL exception to a custom exception
- Handle the exception and continue processing
- Propagate the exception to the upper tiers
The best practice is to propagate the SQL exception to the upper tiers to allow centralized handling and logging, providing a clear separation of concerns in a multi-tier application.
How do you differentiate between checked and unchecked SQL exceptions?
- Checked exceptions are SQLExceptions
- Checked exceptions are caught at compile-time
- Unchecked exceptions are SQLExceptions
- Unchecked exceptions are caught at compile-time
Checked SQL exceptions are those derived from SQLException, and they must be either caught or declared to be thrown. Unchecked SQL exceptions are those that extend RuntimeException.
What is the significance of the finally block in JDBC operations?
- To handle exceptions
- To improve performance
- To optimize code execution
- To release resources
The finally block in JDBC operations is significant for releasing resources, ensuring that resources like database connections are properly closed, regardless of whether an exception occurs.
How can you handle a situation where a database connection is lost during a transaction?
- Commit the transaction
- Ignore the issue and proceed
- Retry the transaction
- Rollback the transaction
If a database connection is lost during a transaction, you can handle it by retrying the transaction, allowing for the re-establishment of the connection and completion of the operation.
Which method is used to retrieve detailed information about an SQL exception?
- getErrorCode()
- getMessage()
- getSQLException()
- getSQLState()
The getErrorCode() method is used to retrieve the specific error code associated with an SQL exception, providing detailed information about the exception.
What is the main purpose of using try-catch blocks in database operations?
- To close connections
- To create databases
- To execute SQL queries
- To handle exceptions
The main purpose of using try-catch blocks in database operations is to handle exceptions that may occur during the execution of SQL queries or other database-related operations.
Which Java statement is used for handling SQL exceptions?
- finally
- if-else
- switch
- try-catch
The try-catch statement is used for handling SQL exceptions in Java. It allows you to catch and handle specific exceptions that may occur during the execution of the code.
What type of exception is commonly thrown when there is a problem with a SQL query in Java?
- ClassNotFoundException
- IOException
- NullPointerException
- SQLException
A SQLException is commonly thrown when there is a problem with a SQL query in Java. It represents a database access error or other errors related to database operations.
How should a system handle a situation where a transaction is interrupted due to a system failure?
- Commit the partial updates
- Ignore the interruption and proceed
- Retry the interrupted transaction
- Rollback the interrupted transaction
If a transaction is interrupted due to a system failure, the system should rollback the interrupted transaction to maintain consistency and avoid partial updates that could lead to data inconsistencies.
In a transaction, if a part of the transaction fails, the ________ operation ensures the database reverts back to its previous state.
- COMMIT
- RELEASE
- ROLLBACK
- SAVEPOINT
The ROLLBACK operation ensures that if any part of a transaction fails, the database reverts back to its previous state, maintaining data consistency.
In JDBC, what does Statement.setFetchSize(int rows) method influence?
- Database table indexing
- Number of rows fetched at a time
- Query execution timeout
- Transaction isolation level
The setFetchSize(int rows) method in JDBC influences the number of rows fetched at a time from the result set, which can impact the performance and memory usage of the application.
The translation of JSP to servlet occurs in the ______ phase.
- Compiling
- Execution
- Initialization
- Parsing
The translation of JSP to servlet occurs in the compiling phase. JSP pages are translated to servlets before they are compiled into bytecode and executed on the server.