Latest Tutorials| Questions and Answers|Ask Questions?|Site Map



Home Answers Viewqa Hibernate composinte primary key in hibernate
Login         

View Questions and Answers by Category

Advertisements


 
Have Programming Question? Ask it here!
 
 
 


suresh anugandula
composinte primary key in hibernate
1 Answer(s)      3 years and 4 months ago
Posted 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.


Advertisement
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>


Related Tutorials/Questions & Answers:
composinte primary key in hibernate
composinte primary key in hibernate  I am facing following problem, Inside the database(mssql), i have created a table without primary key... primary key with all the columns of the table and hibernate s/w has created two pojo
Create primary key using hibernate
Create primary key using hibernate  How to create primary key using hibernate?   The id element describes the primary key for the persistent class and how the key value is generated.   <id name="id
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
How to create primary key using hibernate?
How to create primary key using hibernate?  Hi, How to create primary key using hibernate? Thanks
Define sequence generated primary key in hibernate
Define sequence generated primary key in hibernate  How to define sequence generated primary key in hibernate?   Use value "sequence" for class attribute for generator tag. <id column="USER_ID" name="id" type
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
primary key and unique key
primary key and unique key  Whats is mean by primary key and unique key
primary key and unique key
primary key and unique key  hello, What's the difference between a primary key and a unique key?   hii, Unique key: column restricts entry of duplicate values but entry of null values is allowed. Primary key
What is a "primary key"?
What is a "primary key"?  What is a "primary key"?   Hi, Here is the answer, A primary key is used to uniquely identify each row... be an artificial field (one that has nothing to do with the actual record). A primary key can
difference between a primary key and a unique key?
difference between a primary key and a unique key?  What's the difference between a primary key and a unique key?   Hi, The column holding the primary key constraint cannot accept null values.whereas column holding
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
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
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
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
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
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
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
Automatic primary Generation in Hibernate - Hibernate
Automatic primary Generation in Hibernate   Hi, Ow primary key is generated automatically in hibernate.give me sample code.Thank u
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
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
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
SQL Alter Table Primary Key tutorial
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
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 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
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
Understanding Hibernate <generator> element
generates the primary key for new record. There are many options provided...; element is used to specify the class name to be used to generate the primary key...; In this case <generator> element do not generate the primary key
Advertisements
 

 

 

DMCA.com