composinte primary key in hibernate

I am facing following problem,

      Inside the database(mssql), i have created a table without primary key. After doing hibernate reverse engineering, by default it has taken composite primary key with all the columns of the table and hibernate s/w has created two pojo classes for that table one is a normal pojo class and another is pojo class for id. Inside the Pojo class id, it has generated properties for all the columns for that table and normal pojo class contains a property for Id pojo class. And i have inserted some records into the table.I have inserted few of the rows with a null value for a column. And i have created a class to retrieve all the records from tha table using hql query. Whenever i call the list() on the Query object it returns a List of pojo class objects. But inside the List object it placed null value for those records which contains a null value for a column instead of getting pojo class object. Please help me in resolving this problem.

I will wait for ur solution.

View Answers

June 14, 2011 at 4:36 PM

Hello Suresh

Lets take a example to undersatnad how to create a composite id in hibernate : First Table :Foo

Columns : 1.name
          2.addrid
          3.age

Note : Foo has two PK-columns: addr_id and name

Second Table name :Address

Column : id

In hibernate this could be mapped as follows :

<class name="Foo" table="foo">
    <composite-id name="id" class="Person">
        <key-property name="name" type="string" column="name"/>
        <key-many-to-one name="address" class="Address" column="addrid"/>
    </composite-id>
    <property name="age" column="age" type="string"/>
</class>

<class name="Address" table="address">
    ...
</class>

Ads

Advertisements

hibernate annotations with composite primary key
hibernate annotations with composite primary key I want to know how to use hibernate annotations in case of composite primary key in one table. I tried like this, I have created a table without primary key. By default mssql has

can we update table in hibernate with out primary key in table?
can we update table in hibernate with out primary key in table? can we update table in hibernate with out primary key in table

Adding A Primary Key to an Existing Table
Adding A Primary Key to an Existing Table Been trying to add a primary key to a MySQL table using Java for two days with no success. I'm new... KEY (SerialNo)"); out.println("Primary key added

SQL Alter Table Primary Key
SQL Alter Table Primary Key Alter a Table Primary Key in SQL modifies the existing table and adds a primary key. Create Table Stu_Table SQL statement to create

changing primary key of parent table
changing primary key of parent table I want to change one primary key from a table where primary key is auto created? How can I do that? I have tried UPDATE person SET personid=3494 WHERE personid=8483; and i get the following

SQL PRIMARY KEY Constraint
SQL PRIMARY KEY Constraint The PRIMARY KEY constraint is used to uniquely identifies each... values. It should contain NULL values. The Table contain a primary key

JDBC insert that returns primary key
JDBC insert that returns primary key How to write code for jdbc insert that returns primary key? Help me fast Thanks Hi, Following code can be used: //Add record into database String queryInsert = "insert

Mysql add primary key
Mysql add primary key Mysql add Primary Key is used to add primary key on the column... of this tutorial illustrate an example from 'Mysql Add Primary Key'. To understand

SQL Primary Key
SQL Primary Key The Primary Key in SQL is used to uniquely identifies each records in a database table. The Primary Key of the Table does not include NULL values

Difference between not null and primary key in mysql
Difference between not null and primary key in mysql Explain not null and primary key in mysql

Mysql Alter Table Primary Key
Mysql Alter Table Primary Key Mysql Alter Table Primary Key is used to remove the primary key from the table and add primary key to the existing other column of table

how tohow to create a table with primary key and foreign keyhow to create a table with primary key and foreign key
how tohow to create a table with primary key and foreign keyhow to create a table with primary key and foreign key how to create a table using java language with primary key and foreign key Hi Friend, A foreign

SQL PRIMARY KEY Constraint
SQL PRIMARY KEY Constraint The PRIMARY KEY constraint is used to uniquely... a unique values. It should contain NULL values. The Table contain a primary key

ModuleNotFoundError: No module named 'django-uuid-primary-key'
ModuleNotFoundError: No module named 'django-uuid-primary-key' Hi...: No module named 'django-uuid-primary-key' How to remove the ModuleNotFoundError: No module named 'django-uuid-primary-key' error? Thanks

Mysql Alter Column Primary Key
Mysql Alter Column Primary Key Mysql Alter Column Primary Key is used to modify table and redefine the Primary Key Column in a table. Understand with Example

How to auto increment primary key in mysql...
How to auto increment primary key in mysql... How to auto increment primary key in mysql... and one more thing i need to get auto increment value in front end each time for inserting the value[JSP

Hibernate generator Element
In this tutorial you will learn about the hibernate's generator element , which is used to auto generate the primary key value

hibernate Foreign key
(255) DEFAULT NULL, City varchar(255) DEFAULT NULL, PRIMARY KEY (P_Id...) NOT NULL, OrderNo int(11) NOT NULL, P_Id int(11) DEFAULT NULL, PRIMARY KEY (O_Id...hibernate Foreign key sir, I am using hibernate in netbeans. I have

query regarding auto increment primary key
query regarding auto increment primary key i want to use s1,s2.... as my auto increment primary key.cant i do this in mysql

inserting into mysql database with uid to be primary key and autoincrement
inserting into mysql database with uid to be primary key and autoincrement hello, i am new to jsp and facing problem in creating a database entry.... In the database table, set the uid as the primary key and auto-increment. Then, whenever

SQL Auto increment Primary Key
SQL Auto increment Primary Key SQL Auto increment Primary Key is used to allow a unique... increment Primary Key'. To understand this example we use a query 'use

Hibernate unique key validation example
Hibernate unique key validation example Hi, How to preform unique key validation in Hibernate application? Thanks Hi, You write a program to check for the presence of the key in database before performing add

Identify correct and incorrect statements or examples about an entity bean's primary key and object identity.
an entity bean's primary key and object identity. Prev Chapter 8... and incorrect statements or examples about an entity bean's primary key and object... of an entity object on the basis of its PRIMARY KEY

Hibernate Load Example
the session.load() method to load an entity by its primary key. Here.... The id is the primary key (identifier) of the entity. Method assumes...Hibernate Load Example - Learn how to use the session.load() method

Mysql Alter Foreign Key
Mysql Alter Foreign Key A Foreign Key is a field that marks to the primary key...,� `contact_name` varchar(50) default NULL,� PRIMARY KEY (`publisher_id

primary storage
primary storage Which of the following is not true for the primary storage? a) It is the part of CPU, b) It allows very fast access of data, c) It is relatively more expensive then other storage devices, d) Can be removed

Primary number
Primary number write a program to find the 100th or nth primary number? import java.util.*; class PrimeNumber{ public static void main(String a[]) { Scanner input=new Scanner(System.in

ModuleNotFoundError: No module named 'primary'
ModuleNotFoundError: No module named 'primary' Hi, My Python... 'primary' How to remove the ModuleNotFoundError: No module named 'primary... to install padas library. You can install primary python with following command

Ads