I'm terribly new to Hibernate. I've googled for two hours but I still can't figure out, how to make JOIN without using HQL, only by criteria. I have tables Clients(cID, name) and Visits(vID, vcID, date). The relation is one to many (one client can visit multiple times). I would also like to do it without setFetchMode. Just Criteria. Do I have to change the mappping xml?
UPDATE:
this is part of my mapping xml:
<class name="Client" table="Clients">
<id name="cID" column="cID"><generator class="native"/></id>
<property name="name" length="10" not-null="true"/>
</class>
<class name="Visit" table="Visits">
<id name="vID" column="vID"><generator class="native"/></id>
<property name="vcID" length="10" not-null="true"/>
<property name="date" length="25" not-null="true"/>
</class>
Having a class Client with a list-attribute "visits" that's mapping to your Visit-Entity:
Criteria criteria = session.createCriteria(Client.class);
criteria.addCriteria("visits");
This would create an inner join between your client-table and your visits-table.
Update:
Here you'll find some good examples: http://docs.jboss.org/hibernate/orm/3.3/reference/en/html/querycriteria.html#querycriteria-associations
Mapping Example
I hardly ever use hibernate mapping xml, however it should read similiar to:
<class name="Client" table="Clients">
<id name="cID" column="cID"><generator class="native"/></id>
<property name="name" length="10" not-null="true"/>
<bag name="visits">
<key column="vcId"/>
<one-to-many class="Visit"/>
</bag>
</class>
Tell Hibernate that there is a property "visits" which represents a one-to-many relationship.
You need to update you mapping:
<class name="Client" table="Clients">
<id name="cID" column="cID"><generator class="native"/></id>
<property name="name" length="10" not-null="true"/>
<!-- Declare Set<Visit> visits in the Client class-->
<set name="visits" lazy="false" cascade="all">
<key column="vcID"/>
<one-to-many class="your.package.Visit"/>
</set>
</class>
<class name="Visit" table="Visits">
<id name="vID" column="vID"><generator class="native"/></id>
<!-- and add "Client client" property to your Visit class -->
<many-to-one name="client" column="vcID" lazy="false"/>
<property name="date" length="25" not-null="true"/>
</class>
Then:
Criteria criteria = session.createCriteria(Visit.class).addCriteria("client")
.add(Restriction.eq(...));
or
Criteria criteria = session.createCriteria(Client.class).addCriteria("visits")
.add(Restriction.eq(...));
And Hibernate will join them automatically.
Related
I'm adding ResourcePermission to the object Report. Each Query object can have in a one-to-one relationship. A Query extends Resource and has ResourcePermission's in a one-to-many (one Query to many Permissions).
I need to add the same property to the Report object associated with the Query because it can have different permissions. When I add the list and the map the one Query to many Permission relationship I get
Caused by: org.hibernate.MappingException: Repeated column in mapping for entity: com.bio.ResourcePermission column: resource_id (should be mapped with insert="false" update="false")
Which I am not understanding why, the Report does not extend Query or Resource and therefore it isn't mapped twice. Can a table just not be the many for multiple one-to-many relationships?
<class name="com.bio.Report" table="REPORT">
<id name="id" type="long" column="id">
<generator class="foreign">
<param name="property">query</param>
</generator>
</id>
<property name="name" column="name"/>
<!--Trying to add this list mapping breaks it-->
<bag name="permissions" table="RESOURCE_PERMISSION">
<key column="resource_id" not-null="true"/>
<one-to-many class="com.bio.ResourcePermission"/>
</bag>
<!-- This query extends Resource-->
<one-to-one name="query" class="com.bio.Query" />
</class>
This is the original item that had ResourcePermissions
<class name="com.bio.Resource" table="RESOURCE">
<id name="id" type="long" column="id">
<generator class="native">
<param name="sequence">SEQ_RESOURCE_AUTO</param>
</generator>
</id>
<bag name="permissions" table="RESOURCE_PERMISSION" lazy="true" batch-size="50" cascade="all-delete-orphan">
<key column="resource_id" not-null="true"/>
<one-to-many class="com.bio.ResourcePermission"/>
</bag>
</class>
The Permission mapping
<class name="com.bio.ResourcePermission" table="RESOURCE_PERMISSION">
<id name="id" type="long" column="id">
<generator class="native">
<param name="sequence">SEQ_RES_PERM_AUTO</param>
</generator>
</id>
<property name="canEdit" column="edit"/>
<property name="canView" column="can_view"/>
<property name="canRun" column="run"/>
<property name="everyone" column="everyone"/>
</class>
I had to set inverse="true" on the Report mapping since the ReportPermission will be responsible for the relationship.
<bag name="permissions" table="RESOURCE_PERMISSION" inverse="true">
<key column="resource_id" not-null="true"/>
<one-to-many class="com.bio.ResourcePermission"/>
</bag>
I have two tables: patient_data and patient_diagnosis
Patient_data contains personal data of patient like: pid (pkey), gender, birth_date
patient_diagnosis contains the diagnosis data of the registered patients. It has fields like: record_id (pkey), pid (fkey to patient_data(pid)), diagnosis_date and other related fields.
Now, I want to join these two tables on pid and have all these fields in a single type of object.
Here is the mapping file:
<hibernate-mapping>
<class catalog="emr" name="in.Models.Emr" table="patient_diagnosis">
<id name="recordid" type="long">
<column name="record_id"/>
</id>
<property name="diagnosisDate" type="timestamp">
<column length="19" name="diagnosis_date" not-null="true"/>
</property>
<property name="snomedTermPrimary" type="long">
<column name="snomed_term_primary" not-null="true" />
</property>
<property name="snomedTermSecondary" type="string">
<column name="snomed_term_secondary" />
</property>
<property name="episodeNo" type="long">
<column name="episode_no" not-null="true" />
</property>
<property name="pid" type="long">
<column name="pid" not-null="true" />
</property>
<join table="patient_data">
<key column="pid"/>
<property name="gender" type="string">
<column name="gender" not-null="true"/>
</property>
<property name="birthDate" type="timestamp">
<column length="19" name="birth_date" not-null="true"/>
</property>
</join>
</class>
</hibernate-mapping>
But, the join applies on patient_diagnosis.record_id = patient_data.pid instead of patient_diagnosis.pid = patient_data.pid i.e. HQL applies on primary key of first table with mentioned column from second table.
Please provide the solution so that join can be applied on mentioned column from first with mentioned column from second table. Or is there another way out?
Please note that in case I didn't create classes for patient_data or patient_diagnosis. But, just Emr class having combination of fields of these tables is created.
Try giving foreign key
<id name="pid" type="java.lang.Long">
<column name="pid" />
<generator class="foreign">
<param name="property">patient_data</param>
</generator>
</id>
I am not sure but maybe this should work.
And
<one-to-one name="patient_data" class="in.Models.Emr"
cascade="save-update"></one-to-one>
Similarly in Join class
<one-to-one name="patient_diagnosis" class="in.Models.Emr"
cascade="save-update"></one-to-one>
I hope this helps you.
How to get only parent without children in Hibernate and without lazy exception, when you trying to access chidlren filed after closing session?
I mean, a kind of pure parent obtainingm but I beed to be sure, that somebody will not obtain them with getter or will not catch a lazy exception.
<class name="com.electronic.commerce.models.Category" table="Category">
<id name="id" type="long" access="property">
<column name="categoryId" length="20"/>
<generator class="native"/>
</id>
<property name="name" column="categoryName" type="string"/>
<property name="parentId" column="categoryParentId" type="long"/>
<bag name="children" table="Category" inverse="true" lazy="true" fetch="select">
<key>
<column name="categoryParentId" not-null="true"/>
</key>
<one-to-many class="com.electronic.commerce.models.Category"/>
</bag>
</class>
Mixed solution
Xml:
<prop key="hibernate.enable_lazy_load_no_trans">false</prop>
Java:
DefaultTransactionDefinition defaultTransactionDefinition = new DefaultTransactionDefinition();
defaultTransactionDefinition.setPropagationBehavior(transactionDefinition);
transactionManager.getTransaction(defaultTransactionDefinition);
I am a new bie to the world of hibernate could you please advise , I was going through one to one relationship in Hibernate,
As per my analysis , one to one hibernate relationships can be established by three ways..
1)Through Join concept
2)Same primary key in both the tables
3)Primary key and foriegn key relationship in both the tables
Please advise , the above three ways to achieve the one to one mapping is correct or I am missing something then please advise, and also please advise that the below hbm mapping files that I am using are correct one.if not then please advise.
1) Through Join concept :-
One way to achieve to one to one relationship is by joining concept , following xml is being used for that
<hibernate-mapping>
<class name="mypack.Person" table="person21">
<id name="personId" type="int">
<generator class="increment">
</generator>
</id>
<property name="name"/>
<join table="personAddress">
<key column="personId"/>
<many-to-one name="address" class="mypack.Address" column="addressId" unique="true" cascade="all"/>
</join>
</class>
<class name="mypack.Address" table="address21">
<id name="id" column="addressId" type="int">
<generator class="increment"/>
</id>
<property name="city"/>
<property name="state"/>
</class>
</hibernate-mapping>
2) Same primary key in both the tables :-
Using same primary key in both the tables , following hbm is being used for that
<class name="mypack.Address" table="address31">
<id name="id" column="addressId" type="int">
<generator class="increment"/>
</id>
<property name="city"/>
<property name="state"/>
</class>
<class name="mypack.Person" table="person31">
<id name="personId" type="int">
<generator class="foreign">
<param name="property">address</param>
</generator>
</id>
<property name="name"/>
<one-to-one name="address" class="mypack.Address"/>
</class>
</hibernate-mapping>
3)Primary key and foriegn key relationship in both the tables :-
Primary key in one table and foriegn key in another table. below is the hbm for this
<hibernate-mapping>
<class name="mypack.Person">
<id name="personId" type="int">
<generator class="increment"/>
</id>
<property name="name"/>
<many-to-one name="address" class="mypack.Address" column="addressId" unique="true" cascade="all"/>
</class>
<class name="mypack.Address">
<id name="id" column="addressId" type="int">
<generator class="increment"/>
</id>
<property name="city"/>
<property name="state"/>
</class>
</hibernate-mapping>
folks please advise.
I really think that join table is overkill here for a one-to-one mapping. For the other 2 solutions, please take a look at the following Hibernate documentation, everything is explained : http://docs.jboss.org/hibernate/orm/3.3/reference/en/html/mapping.html#mapping-declaration-onetoone.
For your second mapping (primary key association), both entities need to define a one-to-one mapping and one side of the relation also needs to specify the attribute constrained="true".
This is how I would write your second mapping :
<class name="mypack.Person" table="PERSONS">
<id name="id" type="int" column="PERSON_ID">
<generator class="increment"/>
</id>
<property name="name" type="string" column="NAME"/>
<one-to-one name="address" class="mypack.Address" cascade="all"/>
</class>
<class name="mypack.Address" table="ADDRESSES">
<id name="id" type="int" column="ADDRESS_ID">
<generator class="foreign">
<param name="property">address</param>
</generator>
</id>
<property name="city" type="string" column="CITY"/>
<property name="state" type="string" column="STATE"/>
<one-to-one name="person" class="mypack.Person" constrained="true"/>
</class>
I am using hibernate 4.1.9. I have Users, and the Users have a list of Accounts, and Accounts have list of Transactions. Here is my hbm.xml
<?xml version="1.0"?>
<class name="User" table="users">
<id name="userId" column="userid">
<generator class="increment"/>
</id>
<property name="username" column="username" not-null="true"/>
<property name="password" column="password" not-null="true"/>
<property name="registerDate" type="timestamp" column="register_date"/>
<list name="accounts" table="accounts" inverse="true" cascade="all">
<key column="userid" not-null="true"/>
<index column="accountid"/>
<one-to-many class="com.joe.data.Account"/>
</list>
</class>
<class name="Account" table="accounts">
<id name="accountId" column="accountid">
<generator class="increment"/>
</id>
<property name="balance" type="big_decimal" column="balance"/>
<property name="lastModified" type="timestamp" column="last_modified"/>
<list name="txns" table="transactions" inverse="true" cascade="all">
<key column="accountId" not-null="true"/>
<index column="transactionId"/>
<one-to-many class="com.joe.data.Transaction"/>
</list>
<many-to-one name="userId" class="User" column="userid" not-null="true"
unique="true" cascade="all"/>
<many-to-one name="accountType" class="AccountType" column="account_type"
not-null="true" cascade="all" unique="true" />
</class>
<class name="Transaction" table="transactions">
<id name="transactionId" column="transactionid">
<generator class="increment"/>
</id>
<property name="description" column="description"/>
<property name="amount" type="big_decimal" column="amount"/>
<property name="dateAdded" column="date_added"/>
<property name="reoccuring" type="numeric_boolean" column="reoccuring"/>
<many-to-one name="category" class="Category" column="category"
not-null="true" cascade="all" unique="true" />
</class>
<class name="Category" table="categories">
<id name="categoryId" column="categoryid"/>
<property name="categoryName" column="categoryname" not-null="true"/>
</class>
<class name="AccountType" table="account_types">
<id name="accountType" column="account_type"/>
<property name="accountName" column="name"/>
</class>
If I leave inverse="true" on the list of accounts (in the User) I get the ConstraintViolationException because the userid is not getting put in the insert query. If I take inverse="true" off of the list of accounts, I get org.hibernate.MappingException: Repeated column in mapping for entity: com.joe.data.Account column: accountid (should be mapped with insert="false" update="false")
To clarify lowercase names are database columns names, camel case are class variable names. I know Transaction class isn't working quite right yet, but if I could get the Accounts to insert I could do the same thing to get the Transactions to insert.
Edit: I added the many-to-one on the Account class and now I am getting another exception where hibernate is complaining about missing a getter for userId in com.joe.data.Account
In order to get inverse="true" work, you need to define many-to-one for User in Account and for Account in Transaction class and mappings.