I have a Java EE Hibernate project, and I'm using MySQL as a database.
I want that when I first time run the project, it will create the database automatically.
This is my hibernate.cnf.xml:
<?xml version='1.0' encoding='utf-8' ?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd" >
<hibernate-configuration>
<session-factory>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost/InternetProject</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
<property name="connection.pool_size">10</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.hbm2ddl.auto">update</property>
<property name="show_sql">true</property>
<mapping class="entities.Business" />
<mapping class="entities.Coupon" />
<mapping class="entities.User" />
<mapping class="entities.LastLogin" />
</session-factory>
</hibernate-configuration>
When I first time run this project on another computer, how can I make the database InternetProject to be created?
According to the config file, it might already do it and I'm not aware to it.
Thanks in advance.
<property name="hibernate.hbm2ddl.auto">create</property>
will create tables. But it will not create database. Change the connection url to generate the database.
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost/InternetProject?createDatabaseIfNotExist=true</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
<property name="connection.pool_size">10</property>
Update : character encoding when creating database
<property name="connection.url">
jdbc:mysql://localhost/InternetProject?createDatabaseIfNotExist=true&useUnicode=yes&characterEncoding=UTF-8
</property>
<property name="hibernate.hbm2ddl.auto">create</property>
will do
Hibernate will not create the database for you, only the tables. To create the database you need to tell MySQL to create it if it does'nt already exist by adding a parameter to the URL. E.g.:
jdbc:mysql://db:3306/mydatabase?createDatabaseIfNotExist=true
There are multiple option for auto property.
create - It creates new tables corresponding mapping or annotation. It drops existing tables and data.
update - It keeps existing data and tables. It updates schema. here we have to take care contrants.
create-drop - It is same like create but once session gets closed it drops everything.
validate - it validates or matches schema with map or annotation. It's valid for Production environment.
<!-- create create-drop validate update -->
<property name="hbm2ddl.auto">update</property>
I hope it helps.
Related
I have this hibernate.cfg.xml:
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">org.postgresql.Driver</property>
<property name="connection.url">
jdbc:postgresql://localhost/DatabaseName?createDatabaseIfNotExist=true
&useUnicode=yes&characterEncoding=UTF-8
</property>
<property name="connection.username">postgres</property>
<property name="connection.password">password</property>
<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">5</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.PostgreSQL9Dialect</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.internal.NoCachingRegionFactory</property>
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">update</property>
<mapping class="com.main.User"/>
</session-factory>
</hibernate-configuration>
which is supposed to create both tables (for the User entity and the database DatabaseName). However, it doesn't create a database and fails with an error on this line:
sessionFactory = configuration.buildSessionFactory();
What can I do to make it autocreate database titled DatabaseName?
To create database you have to create is manually you can use IDEs for that or cmd to create your DB
And To create Tables you can use create in place of update
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">create</property>
It will create a schema and then you will use an update for the next startup if you don`t want to recreate your tables
Need some clarification and helps. Especially appreciate describing general concepts or link where they are described.
So, on the hibernate website I have read the next one:
For use inside an application server, you should almost always
configure Hibernate to obtain connections from an application server
javax.sql.Datasource registered in JNDI. You will need to set at least
one of the following properties:
And I have a few question because at the moment I am really confused about all of that stuff with DataSource, DataDriver, Tomcat and Hibernate in general.
Does configuring Datasource and binding SessionFactory to the JNDI
is the same process?
If no, for what we use DataSource and for why we need to bind SessionFactory to JNDI (in general)?
Am I understood right? If we configure DataSource in hibernate.cfg.xml file we don't need to configure it in {tomcat}/conf/server.xml or {tomcat}/conf/context.xml?
What is hibernate.jndi.url? Does it is the same as hibernate.connection.url?
What is hibernate.connection.datasource? In docs I read that it is "datasource JNDI name", so if I understood right it can be any name?
From Hibernate docs I read that setting at least one of the properties hibernate.connection.datasource, hibernate.jndi.url, hibernate.jndi.class, hibernate.connection.username, hibernate.connection.password makes my app use javax.sql.Datasource registered in JNDI. So does the next conf already configured to use DataSource?
How to check that DataSource used and configured fine?
My hibernate.cfg.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.show_sql">true</property>
<property name="hibernate.use_sql_comments">true</property>
<property name="hibernate.format_sql">true</property>
<property name="hibernate.generate_statistics">true</property>
<!--http://stackoverflow.com/questions/2067526/hibernate-connection-pool-->
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<!--For use inside an application server, you should almost always configure Hibernate to obtain connections from an application server javax.sql.Datasource registered in JNDI. You will need to set at least one of the following properties:-->
<!--hibernate.connection.datasource,hibernate.jndi.url,hibernate.jndi.class,hibernate.connection.username,hibernate.connection.password-->
<!--Datasource config-->
<property name="hibernate.connection.datasource">jdbc:mysql://localhost/easywordweb</property>
<!--<property name="hibernate.jndi.url">??????? what is it</property>-->
<!--/Datasource config-->
<!--*****************************************************************-->
<!--C3P0 config-->
<!--Hibernate will obtain and pool connections using java.sql.DriverManager if you set the 5 following properties -->
<!--hibernate.connection.driver_class,hibernate.connection.url,hibernate.connection.username,hibernate.connection.password,hibernate.connection.pool_size-->
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost/easywordweb</property>
<property name="hibernate.connection.username">username</property>
<property name="hibernate.connection.password">password</property>
<!--We can use a third party pool for best performance and stability, for example c3p0. Just replace the hibernate.connection.pool_size property with connection pool specific settings. This will turn off Hibernate's internal pool. For example, you might like to use c3p0. -->
<!--<property name="hibernate.connection.pool_size">140</property>-->
<property name="hibernate.c3p0.max_size">140</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.acquire_increment">5</property>
<!--max to cache-->
<property name="hibernate.c3p0.max_statements">50</property>
<!--The seconds a Connection can remain pooled but unused before being discarded. Zero means idle connections never expire. Hibernate default: 0-->
<property name="hibernate.c3p0.timeout">21600</property>
<!--for test, change futher-->
<property name="hibernate.c3p0.preferredTestQuery">SELECT 1;</property>
<!--at every connection checkin to verify that the connection is valid-->
<property name="hibernate.c3p0.testConnectionOnCheckout">true</property>
<!--at every connection checkout to verify that the connection is valid-->
<property name="hibernate.c3p0.testConnectionOnCheckin">true</property>
<!--/for test, change futher-->
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<!--/C3P0 config-->
<!--*****************************************************************-->
<property name="hibernate.c3p0.validate">true</property>
<!--c3p0 will test all idle, pooled but unchecked-out connections, every this number of seconds-->
<property name="hibernate.c3p0.idle_test_period">21000</property>
<property name="hibernate.jdbc.batch_size">20</property>
<!--Number rows to be returned if no setted-->
<property name="hibernate.jdbc.fetch_size">20</property>
<property name="hibernate.jdbc.use_get_generated_keys">true</property>
<property name="hibernate.temp.use_jdbc_metadata_defaults">false</property>
<!--FIXING: Table "...".hibernate_sequence table not found.-->
<property name="hibernate.id.new_generator_mappings">false</property>
</session-factory>
</hibernate-configuration>
Thank's everyone in advance.
In the config you have posted you are initializing the connection pool within your application.
An alternative is to delegate the creation of the database pool to your app/web server and expose it as a JNDI resource. Your application need then only specify the name of the JNDI datasource to obtain a connection.
Doing this in Tomcat is documented here:
https://tomcat.apache.org/tomcat-6.0-doc/jndi-datasource-examples-howto.html
Your hibernate.cfg.xml then looks like:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.show_sql">true</property>
<property name="hibernate.use_sql_comments">true</property>
<property name="hibernate.format_sql">true</property>
<property name="hibernate.generate_statistics">true</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- The Server configured JNDI datasource -->
<property name="hibernate.connection.datasource">java:comp/env/jdbc/MyLocalDB</property>
<property name="hibernate.jdbc.batch_size">20</property>
<!--Number rows to be returned if no setted-->
<property name="hibernate.jdbc.fetch_size">20</property>
<property name="hibernate.jdbc.use_get_generated_keys">true</property>
<property name="hibernate.temp.use_jdbc_metadata_defaults">false</property>
<!--FIXING: Table "...".hibernate_sequence table not found.-->
<property name="hibernate.id.new_generator_mappings">false</property>
</session-factory>
</hibernate-configuration>
I have mysql DB with UTF-8 and application written in java with hibernate. When I run the application in eclipse everything is fine. But in production which is on a different machine the values returned from DB are corrupted.
I print the values to log (immediately after getting them) and I clearly see that the values I get from DB are corrupted in production.
The DB itself is the same DB for both environments. The values are stored fine.
Any ideas what can be the reason for this?
UPDATE:
I forgot to say that it happens sometimes. I think that in 50% of the times it works fine.
UPDATE 2:
Here is the hibernate.cfg.xml:
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://myDB:3306/myApp?autoReconnect=true&useUnicode=true&createDatabaseIfNotExist=true&characterEncoding=utf-8</property>
<property name="hibernate.connection.username">username</property>
<property name="hibernate.connection.password">password</property>
<!-- <property name="hibernate.connection.pool_size">10</property> -->
<property name="hibernate.connection.isolation">2</property>
<property name="show_sql">true</property>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.hbm2ddl.auto">update</property>
<property name="hibernate.connection.provider_class">com.zaxxer.hikari.hibernate.HikariConnectionProvider</property>
<property name="hibernate.hikari.minimumIdle">5</property>
<property name="hibernate.hikari.maximumPoolSize">10</property>
<property name="hibernate.hikari.idleTimeout">30000</property>
<mapping class="someclass1"/>
<mapping class="someclass2"/>
<mapping class="someclass3"/>
<mapping class="someclass4"/>
</session-factory>
</hibernate-configuration>
Reference URL: https://docs.jboss.org/exojcr/1.12.13-GA/developer/en-US/html/ch-db-configuration-hibernate.html
Please verify the datasource configuration in your production environment whether the attributes - useUniCode and characterEncoding are set properly. Example:
<property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/exodb?relaxAutoCommit=true&autoReconnect=true&useUnicode=true&characterEncoding=utf8"/>
After few years of PHP I decided to learn Java, so I'm writing simple desktop app that uses Hibernate and SQLite.
I'd like to keep database outside of the .jar generated by mvn package, so one can perform quick backup of the data just by copying one file. So far, my hibernate.cfg.xml looks like this:
<hibernate-configuration>
<session-factory>
<property name="show_sql">true</property>
<property name="format_sql">true</property>
<property name="dialect">org.hibernate.dialect.SQLiteDialect</property>
<property name="connection.driver_class">org.sqlite.JDBC</property>
<property name="connection.url">jdbc:sqlite:mydb.db</property>
<property name="connection.username"></property>
<property name="connection.password"></property>
<property name="hibernate.hbm2ddl.auto">update</property>
<mapping class="com.ex3v.hibernate.Contact"/>
</session-factory>
</hibernate-configuration>
what connection.url do I have to specify to make hibernate create db file next to .jar in working directory?
You can find your answer here:
Just a summary from above site,
different formats are :
jdbc:sqlite:mydb.db
jdbc:sqlite://dirA/dirB/mydb.db
jdbc:sqlite:/DRIVE:/dirA/dirB/mydb.db
jdbc:sqlite:///COMPUTERNAME/shareA/dirB/mydb.db
Use relative path like this.
jdbc:sqlite:./DB/mydb.db
I have created Java application using Hibernate with this configuration:
<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306 /bee</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.query.factory_class">org.hibernate.hql.classic.ClassicQueryTranslatorFactory</property>
<property name="connection.username">root</property>
<property name="connection.password"/>
<property name="hibernate.connection.charSet">UTF-8</property>
<property name="hibernate.connection.characterEncoding">UTF-8</property>
<property name="hibernate.connection.useUnicode">true</property>
<mapping resource="DatabaseMapping.hbm.xml"/>
</session-factory>
</hibernate-configuration>
Everything works fine when Iam using jdbc:mysql://localhost..., but now I need to have the database embedded in my application. Which database should I use? I need to have all my data stored and load it after start the application, update data, save, delete. I use HQL query or SQL query.
What is the simplest way to make the database embedded? I don´t want to change my queries. It would be fine to change only hibernate configuration and set it to the embedded database, is it possible?
One of the advantages of ORM's like Hibernate is to shield you from DB differences. You can use any one of the below as an embedded DB solution. Just change the dialect, driver and URL in hibernate cfg file.
H2
SQLite
HSQLDB
Hava a look at using the H2 database in embedded mode
<hibernate-configuration>
<session-factory>
<property name="hibernate.connection.driver_class">org.h2.Driver</property>
<property name="hibernate.connection.url">jdbc:h2:~/test</property>
<property name="hibernate.dialect">org.hibernate.dialect.H2Dialect</property>
<property name="hibernate.query.factory_class">org.hibernate.hql.classic.ClassicQueryTranslatorFactory</property>
<property name="connection.username">sa</property>
<property name="connection.password"/>
<property name="hibernate.connection.charSet">UTF-8</property>
<property name="hibernate.connection.characterEncoding">UTF-8</property>
<property name="hibernate.connection.useUnicode">true</property>
<property name="hibernate.default_schema">PUBLIC</property>
<mapping resource="DatabaseMapping.hbm.xml"/>
</session-factory>
</hibernate-configuration>
If you don't want to change your queries, consider mysql-mxj (embedded mysql) http://dev.mysql.com/doc/connector-mxj/en/connector-mxj.html
It is not under active development (thanks Oracle). But is prefectly usable and the connector is open source. It is trivial to embed different versions of mysql, but the latest mxj connector embeds 5.5.9