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Postgres database setting to allow ddl generation

I have two Postgres databases, one for Dev and one for Prod. I also have a Java/Hibernate application that has the following:
persistence.xml
<persistence-unit name="pims">
<jta-data-source>jdbc/pims</jta-data-source>
<properties>
<!-- For JBoss / Hibernate -->
<property name="hibernate.hbm2ddl.auto" value="update" />
<!-- For Glassfish / Toplink -->
<property name="toplink.ddl-generation" value="create-tables"/>
</properties>
</persistence-unit>
Problem
When the JBoss server starts in the Prod environment, it creates the new tables as expected. But when it starts in the DEV environment (same code), it does not create the new tables.
This makes me think there is some setting on the database that prevents the creation of the new tables.
Question
Is there any config on the database that will prevent JPA/Hibernate from creating the new tables?
More Info:
Java 1.7
Struts 1
Hibernate 4.2.21.Final
PostgreSQL 8.0
Connection:
<jndi-name>jdbc/pims</jndi-name>
<connection-url>jdbc:postgresql://localhost:5432/pims</connection-url>
<driver-class>org.postgresql.Driver</driver-class>
<user-name>postgres</user-name>
Users:
DEV
PROD

Configuration of persistence.xml while using websphere 8.5.5.1

I'm coding an app that uses Servlet 3.0, Jsp, and JPA 2.0 and i'm deploying it into Websphere application server 8.5.
Since i already configured into the ibm websphere console, the data source and the jdbc driver, and the j2c authentification (i'm using oracle 11g as a database ). I dont know how my persistence.xml should look like, if i need to specify and add openJPA jars to my project.
For now anything i put into persistence.xml i'm having this issue :
Error 500: <openjpa-2.2.3-SNAPSHOT-r422266:1764177 fatal user error> org.apache.openjpa.persistence.ArgumentException
What should i do ? maybe i'm missing how JPA works
Thanks in advance

The OpenJPA jars should be provided by WebSphere and available to use for your application. There is a JPA sample available here: https://developer.ibm.com/wasdev/downloads/#asset/samples-Java_Persistence_API_JPA_Sample
In the sample, you can see an example of the persistence.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0"
xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="jpasamplepersistenceunit">
<jta-data-source>java:comp/env/jdbc/samplejpadatasource</jta-data-source>
<non-jta-data-source>java:comp/env/jdbc/samplejpadatasourcenonjta</non-jta-data-source>
<class>wasdev.sample.jpa.Thing</class>
<exclude-unlisted-classes>true</exclude-unlisted-classes>
<properties>
<!-- These properties are creating the database on the fly. We are using them to avoid users having
to create a database to run the sample.
See also the create=true line in the datasource meta data. -->
<property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema(ForeignKeys=true)" />
<property name="openjpa.jdbc.DBDictionary" value="derby" />
<!-- EclipseLink specific properties to create the database. They are only used if using the jpa-2.1 feature. -->
<property name="eclipselink.ddl-generation" value="drop-and-create-tables" />
<property name="eclipselink.ddl-generation.output-mode" value="both" />
</properties>
</persistence-unit>
</persistence>
I think your error is not caused by the OpenJPA jars not being available. It might be because your database is not configured correctly. Make sure your persistence.xml file refers to your datasources properly.

Wildfly Data Persistence

I am currently working on a Java EE project and am working with the Wildfly server.
I have a Web project and EJB project which are deployed onto the Wildfly server.
I can save a user for example, but only for as long as the server is running.
There is no data persistence between server downtimes.
I have searched through the internet but couldn't find an answer.
My persistence.xml looks like this:
<persistence-unit name="primary">
<!-- If you are running in a production environment, add a managed
data source, this example data source is just for development and testing! -->
<!-- The datasource is deployed as WEB-INF/kitchensink-quickstart-ds.xml, you
can find it in the source at src/main/webapp/WEB-INF/kitchensink-quickstart-ds.xml -->
<jta-data-source>java:jboss/datasources/ExampleDS</jta-data-source>
<properties>
<!-- Properties for Hibernate -->
<property name="hibernate.hbm2ddl.auto" value="create-drop" />
<property name="hibernate.show_sql" value="false" />
<value="true"/>
</properties>
If I want to persist any information, do i need to reconfigure this file?
I hope you can help me :)

Your problem is this line
<property name="hibernate.hbm2ddl.auto" value="create-drop" />
Everytime when the wildfly starts up, JPA creates a new database model with an empty database.
Adjust your code to
<property name="hibernate.hbm2ddl.auto" value="update" />

You are using "ExampleDS" which is set up as H2 in-memory database by default. It therefore does not persist data between restarts on purpose (useful for development/testing). Go to wildfly's standalone/configuration/standalone.xml configuration file and search for "ExampleDS" in the "datasources" section. It should show:
<connection-url>jdbc:h2:mem:test;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE</connection-url>
where "mem" means in-memory. You can change "mem:test" to any write path, e.g.
<connection-url>jdbc:h2:~/test;DB_CLOSE_DELAY=-1</connection-url>
to use a H2 file-based database stored as "test" in your home-folder (assuming *nix).
You can also define additional databases (Postgresql, Oracle, etc) in the datasources-section.

Cannot load JDBC driver class 'com.mysql.jdbc.GoogleDriver'

I am facing a very bizarre problem where my App Engine server can't load its Cloud SQL's GoogleDriver, here's the error (It happens right after I run "mvn appengine:update").
org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.exception.GenericJDBCException: Cannot open connection
at org.springframework.orm.hibernate3.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:596)
...
Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot load JDBC driver class 'com.mysql.jdbc.GoogleDriver'
at org.apache.commons.dbcp.BasicDataSource.createConnectionFactory(BasicDataSource.java:1429)
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1371)
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
at org.springframework.orm.hibernate3.LocalDataSourceConnectionProvider.getConnection(LocalDataSourceConnectionProvider.java:81)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
... 48 more
Caused by: java.lang.ClassNotFoundException: com.mysql.jdbc.GoogleDriver
appengine.properties
################### MySQL Configuration - Google Cloud App Engine ##########################
jdbc.driverClassName=com.mysql.jdbc.GoogleDriver
jdbc.url=jdbc:google:mysql://mytestapp:testdb?user=someuser
jdbc.username=someuser
jdbc.password=******
jdbc.dialect=org.hibernate.dialect.MySQLDialect
In my Spring context file I have:
<context:property-placeholder location="classpath:appengine.properties" />
<bean
id="dataSource"
class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close" >
<property
name="driverClassName"
value="${jdbc.driverClassName}" />
<property
name="url"
value="${jdbc.url}" />
...
Any ideas?
==
Just to confirm, I had already configured my appengine-web.xml and it doesn't help at all:
<?xml version="1.0" encoding="utf-8"?>
<appengine-web-app xmlns="http://appengine.google.com/ns/1.0">
<application>mytestapp</application>
<version>1</version>
<threadsafe>true</threadsafe>
<sessions-enabled>true</sessions-enabled>
<system-properties>
<property name="java.util.logging.config.file" value="WEB-INF/logging.properties"/>
</system-properties>
<use-google-connector-j>true</use-google-connector-j>
</appengine-web-app>
--
I couldn't move forward due to some incompatibility between hibernate jar versions so I kept trying through the actual release pipeline (Jenkins + Maven + build + test + deploy), I had to add the Compute Engine VM's IP address to the list of authorized IPs of the Cloud SQL Instance in order to run my unit tests and deploy it to the application (but, if I keep this approach, I can only use the MySQL driver and URL instead of the GoogleDriver and URL. So this is getting tricky...).
I have these properties in a Production.properties file that is loaded by my Spring MVC config file:
################### MySQL Configuration - Google Cloud App Engine ##########################
jdbc.driverClassName=com.mysql.jdbc.GoogleDriver
jdbc.url=jdbc:google:mysql://*******testapp:testsqldb?user=root
jdbc.username=root
jdbc.password=*****
jdbc.dialect=org.hibernate.dialect.MySQLDialect
Is there an easy way to dynamically switch between external and GAE Cloud SQL connection details without using this approach?
if (SystemProperty.environment.value() ==
SystemProperty.Environment.Value.Production) {
// Connecting from App Engine.
Any ideas?

The class is not automatically available in the App Engine runtime. You must enable it by adding <use-google-connector-j>true</use-google-connector-j> to your appengine-web.xml. This is documented at: https://cloud.google.com/appengine/docs/java/cloud-sql/#enable_connector_j
Edited to add (from comments below):
Also, when connecting to Cloud SQL from GAE you should leave the password field empty.
You should also make sure that if your code is running outside GAE (e.g. on your workstation, on GCE, on a Jenkins build) it uses stock MySQL connector as the Google connector is only available on GAE.
You might also want too look into using the stock MySQL driver, which works both from GAE and other connections. There is a demo of this at https://github.com/GoogleCloudPlatform/appengine-cloudsql-native-mysql-hibernate-jpa-demo-java

How to use HSQLdb with Ibatis

I want to use in memory database to query for data in my unit testing, my project is Ibatis (with annotation) for querying actual database which I want to mimic with the help of HSQLDB.
Please help me with how to configure iBatis with HSQLDB.
Also is there any way to these better for unit testing with code which is strongly dependent on database in its functions.

You can make an iBatis sqlMappings.xml config file something like this:
<sql-map-config>
<properties resource="configuration.properties" />
<!--The datasource for you application is configured here: -->
<datasource name = "hsql"
factory-class="com.ibatis.db.sqlmap.datasource.SimpleDataSourceFactory"
default="true">
<property name="JDBC.Driver" value=""/>
<property name="JDBC.ConnectionURL" value=""/>
<property name="JDBC.Username" value=""/>
<property name="JDBC.Password" value=""/>
</datasource>
<!--Declare the SQL Maps to be loaded for this application.
Be sure it's in your classpath. -->
<sql-map resource="maps/beanMappings.xml"/>
</sql-map-config>
plus a congifuration.properties file like this:
JDBC.Driver=org.hsqldb.jdbcDriver
JDBC.ConnectionURL=jdbc:hsqldb:hsql://localhost/myDb
JDBC.Username=sa
JDBC.Password=
and then use it like this:
String resource = "maps/SqlMapConfig.xml";
Reader reader = Resources.getResourceAsReader(resource);
SqlMap sqlMap = XmlSqlMapBuilder.buildSqlMap(reader);