JDBC Interview Questions and Answers
Question - 111 : - What is savepoint and what are the methods we have in JDBC for savepoint?
Answer - 111 : -
Savepoint is used to create checkpoints in a transaction, and it allows us to perform a rollback to the specific savepoint. Once the transaction is committed or rolled backed, the savepoint that has been created for a transaction will be automatically destroyed and becomes invalid.
Methods for Savepoint:
- setSavepoint() method: It is used to create Savepoint, we can use the rollback() method to undo all the changes till the savepoint.
- releaseSavepoint() method: It is used to remove the given savepoint.
Answer - 112 : -
- SQLNonTransientException
- SQLTransientException
- SQLRecoverableException
Question - 113 : - What is batch processing and how to do it in JDBC?
Answer - 113 : -
Batch processing is the process of executing several SQL statements in one transaction. Doing so will reduce communication time and increase performance. It makes processing a large amount of data much easier.
Advantages of Batch Processing:
Improve performance
Data consistency
How to perform Batch Processing:
We have addBatch() and executeBatch() methods in Java to perform Batch processing. These 2 methods are present in Statement and PreparedStatement classes.
Question - 114 : - What is the stored procedure?
Answer - 114 : - A group of SQL queries that are executed as a single unit to perform a particular task is known as a Stored Procedure. We can pass 3 different types of parameters. Each procedure is represented by its name. So the name of the procedure should be unique.
Question - 115 : - What are the parameter types in Stored Procedures?
Answer - 115 : -
There are three types of parameters available in Stored Procedures. They are:
- IN: Used to pass the input values to the procedure.
- OUT: Used to get the value from the procedure.
- IN/OUT: Used to pass the input values and get the value to/from the procedure.