Reasons to Choose Hibernate Over JDBCHey Java Developer,Have you ever felt irritated by repeating the same lines of code over and over again in your application for fetching data from a database Are you struggling to map objects to your database tablesIs it difficult for you to implement oops with your JDBC code Does it takes too much rework while migrating from one database to anotherHave you ever found it difficult to create associations between tables using JDBC If you are wondering whether there is a way to avoid these problems, I am very much pleased to inform you that there is an ORM tool called Hibernate that you can use to overcome this. Before getting into that, I would like to explain what is Hibernate and JDBC. What Is JDBC             JDBC stands for Java Database Connectivity. It is a free open source application programming interface for Java that enables applications to access databases. It enables developers to create queries and update data to a relational database using the Structured Query Language SQL. JDBC Workflow. Source avaldes. Open a database connection. Send SQL queries to database using a JDBC driver. Hibernate Sessions Learn Hibernate in simple and easy steps starting from basic to advanced concepts with examples including Overview, Architecture, Environment. The return value of session. Most likely you have a type of ID that isnt a Long. Try doing this System. Spring 4 MVC with Hibernate 4 MySQL Integration Example annotation based to create a CRUD oriented web application, making use of AOP based transactions. Hibernate Save Or Update Return Id' title='Hibernate Save Or Update Return Id' />Hi lokesh, I want to create a criteria for this but I dont have much knowledge about hibernate criteria. I have 3 tables REGISTRATIONTBLUSERID,EMAILID. The session. saveobject returns the id of the object, or you could alternatively call the id getter method after performing a save. Save return value. HibernateORMHibernatejava ORM. In this tutorial, we show you how to use Hibernate to implements manytomany table relationship, with extra column in the join table. The STOCK and CATEGORY. JDBC driver connects to the database. Execute the queries to get the result set. Send the data to the application via the driver manager. When results are returned, it processes the data. Finally, the connection is closed. What Is Hibernate Source J2eebrain. LxFGD.jpg' alt='Hibernate Save Or Update Return Id' title='Hibernate Save Or Update Return Id' />Hibernate is a free, open source object relational mapping library for Java designed to map objects to an RDBMS and to implement the object oriented programming concepts in a relational database. Hibernate Workflow. Source Cloudsopedia. Unlike JDBC, Hibernate connects with the database itself and uses HQL Hibernate Query Language to execute the queries, then maps the results to Java objects. The results are mapped to objects based on the properties given in the Hibernate configuration XML file. The database connection from an application is created using the session, which also helps in saving and retrieving the persistent object. Session factory is an interface that helps to create an instance of a session. There must be only one session factory per database. For example, if you are using My. SQL and Oracle in your application, one session factory for My. SQL and one session factory for Oracle is maintained. There will not be more than one session factory for My. SQL alone. So, without further ado, lets take a look at all the reasons why you should consider Hibernate over JDBC. Impedance Mismatch. Hibernate mainly solves the object relational impedance mismatch problems that arise when a relational database is connected by an application written in an object oriented programming language style. Object relational impedance mismatches arise due to data type differences, manipulative differences, transactional differences, and structural and integrity differences. Click here to see more details. Object Mapping. In JDBC, you need to write code to map the object models data representation to a relational model and its corresponding schema. Hibernate itself maps Java classes to database tables using XML or by using annotations. The following example will help you understand how object mapping is done in Hibernate              JDBC. Listlt User usersnew Array. Listlt User. User user new User. User. Idrs. get. StringUser. Id. Namers. get. StringFirst. Name. user. set. Emailrs. StringEmail. Tablename user. User. Model. Generated. Valuestrategy Generation. Type. IDENTITY. private Big. Integer id. Columnname email, unique true. String email. Columnname name. String name. public Big. Integer get. Id. IdBig. Integer id. String get. Email. EmailString email. String get. Name. NameString name. In the above example, you can see that by using JDBC, you need to set every property of an object upon fetching the data each and every time. But in Hibernate, we need to map the table with the Java class as mentioned above. HQLHibernate uses HQL Hibernate Query Language, which is similar to SQL, but Hibernates HQL provides full support for polymorphic queries. HQL understands object oriented concepts like inheritance, polymorphism, and association. For a detailed understanding of polymorphic HQL queries, refer to this link. Database Independent. Hibernates code is database independent because you do not need to change the HQL queries with a few exceptions when you change databases like My. SQL, Oracle, etc. Hence, it is easy to migrate to a new database. It is achieved by using a friendly dialect to communicate with the database. The database can be specified using a dialect in the Hibernate configuration XML as follows. My. SQLlt property For example, consider the following scenario. You need to fetch the first 1. How this is implemented in different databases is explained below My. SQL. SELECT columnname FROM tablename ORDER BY columnname ASC LIMIT 1. SELECT TOP 1. 0 columnname FROM tablename ORDER BY columnname ASC. In Hibernate, this can be done as follows. Session. Create. QuerySELECT E. FROM Employee E ORDER BY E. ASC. Set. Max. Results1. List. Thus your query statement need not change, irrespective of the database you are using. Minimize Code Changes. Hibernate minimizes code changes when we add a new column to a database table. JDBCYou have to add a new field in your POJO class. Change your JDBC method that performs the select to include the new column. Change your JDBC method that performs the insert to add a new value into the new column. Change your JDBC method that performs the update to update an existing value in your new column. Hibernate. Add the new field into your POJO class. Modify the Hibernate XML mapping file to include the new column. Thus, database table changes can be easily implemented using Hibernate with less effort. Reduce Repeat Code. Hibernate reduces the amount of repeating lines of code, which you can often find with JDBC. For your understanding, I have left a simple scenario below. Class. for. Namecom. Driver. Connection con Driver. Manager. get. Connection jdbc mysql localhost 3. Prepared. Statement stmtcon. Statementinsert into Emp values,. Best Chess Software For Windows 7. Int1,1. 01. stmt. String2,Ratan. Update. In JDBC, as mentioned above for inserting a record, you will be creating a prepared statement and will be setting each column of a table. If the number of columns increases, the statements will also increase. But in Hibernate, we just need to save the object with persistObject. Lazy Loading. We can achieve lazy loading using Hibernate. Consider an example where there is a list of users in the user table. The identity proof documents uploaded by the users are stored in the identityproof table. The user has a one to many relationships with the identityproof. In this case, the user is the parent class and identityproof is the child class. If you fetch the parent class, i. Imagine the size of each document. As the number of documents increases, the size of data to be processed also increases, and hence it will slow up the application. With Hibernate, you can specify the fetch type for data as LAZY. If you do so when you fetch a user, documents will not be fetched. You can fetch the documents where you want using Hibernates initialize method. Declaring fetch type for one to many association in your POJO. One. To. Manycascade Cascade. Type. ALL, fetch Fetch. The session. saveobject returns the id of the object, or you could alternatively call the id getter method after performing a save. Save return value Serializable saveObject object throws Hibernate. Exception. Returns the generated identifier. Getter method example User. Details entity Entity. User. Details. Generated. Value. private int id. String name. Constructor, Setters Getters. Logic to test the ids Session session Hibernate. Util. get. Session. Factory. get. Current. Session. session. Transaction. begin. User. Details user. User. Detailsuser. User. Details user. User. Detailsuser. Id Integer session. System. out. printlnbefore save user ids user. Id, user. Id. session. System. out. printlnafter save user ids user. Id, user. Id. session. Transaction. commit. Output of this code before save user ids 0, 0after save user ids 1, 2. As per this output, you can see that the ids were not set before we save the User. Details entity, once you save the entities then Hibernate sets the ids for your objects user.