Hibernate Interview Questions and Answers For Experienced
Q1. What is the difference among sorted and ordered collection in hibernate?
Ans: Sorted Collection: The taken care of collection is a group this is looked after the usage of the Java collections framework. The sorting is performed inside the memory of JVM that is running hibernate, quickly after analyzing the information from the database using Java Comparator The less the collection the extra the efficient of sorting
Ordered Collection: The order collections will also types a collection by means of the use of the order by way of clause for the effects fetched.The extra the collection, the more green of sorting
Q2. Describe your favorite element of the Hibernate framework.
Ans: There are plenty to select from, but I’d say my favored factor is that Hibernate is that it’s an item-oriented question language.
There are numerous capability answers to this query. The interviewer just wants to see wherein your values lie.
Q3. Explain the principle difference between Entity Beans and Hibernate.
Ans: Entity beans are to be applied through packing containers, instructions, descriptors. Hibernate is only a tool that quickly persist the item tree to a category hierarchy in a database and with out the usage of a unmarried SQL assertion. The inheritance and polymorphism is quite clearly implemented in hibernate which is out of the field of EJB and a massive downside.
Q4. What is your least favorite thing of the Hibernate framework?
Ans: It does plenty of factors proper, but I frequently discover myself having to jot down boilerplate code while the use of Hibernate. The verbosity of the language makes my activity greater hard.
Once once more, the interviewer wants to see where your values lie.
Q5. Explain the distinction among Hibernate and Spring.
Ans: Hibernate is an ORM tool for facts persistency. Spring is a framework for business enterprise programs. Spring helps hibernate and offers the specific training which are templates that contains the commonplace code.
Q6. Does a Session object use a first-stage cache or a 2d-level cache?
Ans: A Session item makes use of a first-degree cache. You’d use a 2d-degree cache if it was a SessionFactory item.
This is a talents question, which makes positive you’ve spent sufficient time with this system to realize its bits and bobs.
Q7. Why hibernate is high-quality over Entity Beans & JDBC?
Ans: An entity bean constantly works below the EJB container, which allows reusing of the item external to the container. An object cannot be detached in entity beans and in hibernate detached items are supported.
Hibernate isn't always database structured wherein as JDBC is database structured. Query tuning isn't wished for hibernate as JDBC is needed. Data can be located in a couple of cache which is supported through hibernate, whereas in JDBC the cache is to be implemented.
Q8. How do you hold your technical know-how?
Ans: I take persevering with schooling instructions. I additionally try to study up on books and magazines. Then of route there are conferences — I try to visit as a minimum one or two a yr, given that they may be so instructional.
The interviewer desires to makes certain which you’re willing to preserve your know-how.
Q9. What is the gain of Hibernate over jdbc?
Ans: The blessings of Hibernate over JDBC are:
Hibernate code will paintings nicely for all databases, for ex: Oracle,MySQL, and so forth. Wherein as JDBC is database specific.
No understanding of SQL is wanted because Hibernate is a hard and fast of objects and a desk is handled as an item, in which as to work with JDBC, one need to recognize SQL.
Query tuning isn't always required in Hibernate. The question tuning is computerized in hibernate by means of using standards queries, and the end result of performance is at its fine. Where as in JDBC the query tuning is to be completed through the database authors.
With the guide of cache of hibernate, the information can be located within the cache for higher overall performance. Where as in JDBC the java cache is to be implemented.
Q10. Name an advantage of the use of POJOs.
Ans: POJOs — which stand for Plain Old Java Objects — are greater green than normal java lessons.
This is a abilities query, which makes positive you’ve spent sufficient time with the program to recognize its bits and bobs.
Q11. State the role of SessionFactory interface performs in Hibernate.
An software obtains Session instances from a SessionFactory that's usually single for the whole application created all through its initialization.
The SessionFactory caches generate SQL statements and other mapping metadata that Hibernate makes use of at runtime.
It additionally holds cached information that has been study in a single unit of labor and can be reused in a future unit of work
SessionFactory sessionFactory = configuration.BuildSessionFactory();
Q12. Name Hibernate’s exclusive forms of collections.
Ans: There’s Order Collection and Sorted Collection.
This is a talents question, which makes positive you’ve spent sufficient time with this system to know its bits and bobs.
Q13. What is Hibernate Query Language (HQL)?
Ans: Hibernate Query Language is designed for records management the usage of Hibernate era. It is completely object oriented and subsequently has notions like inheritance, polymorphism and abstraction. The queries are case-touchy. This has an exception for Java instructions and houses. The question operations are via items. HQL acts as a bridge among Objects and RDBMS.
Q14. Name Hibernate’s 3 object states.
Ans: Detached, Transient, and Persistent.
This is a competencies query, which makes certain you’ve spent sufficient time with this system to recognise its fine details.
Q15. Explain the blessings and downsides of indifferent objects.
Detached items passing can be achieved throughout layers upto the presentation layer without the use of Data Transfer Objects.
At the time of the usage of lengthy transactions with the aid of the consumer which desires lengthy assume-time, it's miles suggested to cut up these transactions into a few transactions. The indifferent items get modified apart from the transaction scope which then may be re-attached to a new transaction.
The usage of indifferent items are cumbersome and cryptic. It is recommended now not to be cluttered with the session, if feasible.
It is recommended to apply DataTransferObjects and DomainObjects this is used to preserve separation among the user interfaces and the Service.