diff --git a/persistence-modules/hibernate-jpa-2/pom.xml b/persistence-modules/hibernate-jpa-2/pom.xml
index 12d6691b1a..8bacdde59c 100644
--- a/persistence-modules/hibernate-jpa-2/pom.xml
+++ b/persistence-modules/hibernate-jpa-2/pom.xml
@@ -24,6 +24,11 @@
             <artifactId>spring-boot-starter-web</artifactId>
             <version>${spring-boot.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-thymeleaf</artifactId>
+            <version>${spring-boot.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-data-jpa</artifactId>
@@ -39,7 +44,6 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
             <version>${spring-boot.version}</version>
-            <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>com.h2database</groupId>
@@ -51,20 +55,41 @@
             <artifactId>hibernate-spatial</artifactId>
             <version>${hibernate.version}</version>
         </dependency>
+        <dependency>
+            <groupId>com.mysql</groupId>
+            <artifactId>mysql-connector-j</artifactId>
+            <version>${mysql.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>ch.vorburger.mariaDB4j</groupId>
+            <artifactId>mariaDB4j</artifactId>
+            <version>${mariaDB4j.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.hibernate</groupId>
             <artifactId>hibernate-testing</artifactId>
             <version>${hibernate.version}</version>
-            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-generator-annprocess</artifactId>
+            <version>${jmh-generator.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>postgresql</artifactId>
+            <version>${postgresql.version}</version>
         </dependency>
     </dependencies>
 
     <properties>
+        <mysql.version>8.2.0</mysql.version>
         <hibernate.version>6.4.2.Final</hibernate.version>
+        <mariaDB4j.version>2.6.0</mariaDB4j.version>
         <spring-boot.version>3.0.4</spring-boot.version>
         <h2.version>2.1.214</h2.version>
         <org.slf4j.version>2.0.7</org.slf4j.version>
         <logback.version>1.4.6</logback.version>
     </properties>
 
-</project>
+</project>
\ No newline at end of file
diff --git a/persistence-modules/hibernate-jpa-2/src/main/resources/META-INF/persistence.xml b/persistence-modules/hibernate-jpa-2/src/main/resources/META-INF/persistence.xml
index 1f91014bd8..26535ee047 100644
--- a/persistence-modules/hibernate-jpa-2/src/main/resources/META-INF/persistence.xml
+++ b/persistence-modules/hibernate-jpa-2/src/main/resources/META-INF/persistence.xml
@@ -3,6 +3,128 @@
              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"
              version="2.0">
+    <!-- Persistence unit for H2 -->
+    <persistence-unit name="com.baeldung.hibernate.entitymanager.game_player_h2">
+        <description>EntityManager getReference persistence unit</description>
+        <class>com.baeldung.hibernate.entitymanager.getreference.Game</class>
+        <class>com.baeldung.hibernate.entitymanager.getreference.Player</class>
+        <exclude-unlisted-classes>true</exclude-unlisted-classes>
+        <properties>
+            <!-- even if we set exclude-unlisted-classes=true, strangely it's not enough to exclude defined hbm files in hibernate.cfg.xml.
+            So, some entities out of the scope unwillingly managed by our persistence unit. In order to prevent this, we disable autodetection
+            of the hbm files completely. When we set this property, hibernate ignores the exclude-unlisted-classes property. -->
+            <property name="hibernate.archive.autodetection" value=""/>
+
+            <property name="hibernate.jpa.compliance.proxy" value="false"/>
+
+            <property name="hibernate.hbm2ddl.auto" value="update"/>
+            <property name="hibernate.show_sql" value="true"/>
+            <property name="hibernate.generate_statistics" value="false"/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
+            <property name="jakarta.persistence.jdbc.driver" value="org.h2.Driver"/>
+            <property name="jakarta.persistence.jdbc.url" value="jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1"/>
+            <property name="jakarta.persistence.jdbc.user" value="sa"/>
+            <property name="jakarta.persistence.jdbc.password" value=""/>
+            <property name="hibernate.id.db_structure_naming_strategy" value="legacy" />
+            <!-- ensure backward compatibility -->
+            <property name="hibernate.type.preferred_duration_jdbc_type" value="BIGINT" />
+            <property name="hibernate.type.preferred_instant_jdbc_type" value="TIMESTAMP" />
+        </properties>
+    </persistence-unit>
+    <!-- Persistence unit for MySQL -->
+    <persistence-unit name="com.baeldung.hibernate.entitymanager.game_player_mysql">
+        <description>EntityManager getReference persistence unit</description>
+        <class>com.baeldung.hibernate.entitymanager.getreference.Game</class>
+        <class>com.baeldung.hibernate.entitymanager.getreference.Player</class>
+        <exclude-unlisted-classes>true</exclude-unlisted-classes>
+        <properties>
+            <!-- even if we set exclude-unlisted-classes=true, strangely it's not enough to exclude defined hbm files in hibernate.cfg.xml.
+            So, some entities out of the scope unwillingly managed by our persistence unit. In order to prevent this, we disable autodetection
+            of the hbm files completely. When we set this property, hibernate ignores the exclude-unlisted-classes property. -->
+            <property name="hibernate.archive.autodetection" value=""/>
+
+            <property name="hibernate.jpa.compliance.proxy" value="false"/>
+
+            <property name="hibernate.hbm2ddl.auto" value="update"/>
+            <property name="hibernate.show_sql" value="true"/>
+            <property name="hibernate.generate_statistics" value="false"/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
+            <property name="jakarta.persistence.jdbc.driver" value="com.mysql.cj.jdbc.Driver"/>
+            <property name="jakarta.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/baeldung"/>
+            <property name="jakarta.persistence.jdbc.user" value="root"/>
+            <property name="jakarta.persistence.jdbc.password" value="password"/>
+
+            <property name="jakarta.persistence.schema-generation.database.action" value="drop-and-create"/>
+            <property name="jakarta.persistence.schema-generation.create-script-source" value="/META-INF/create-db.sql"/>
+            <property name="jakarta.persistence.schema-generation.drop-script-source" value="/META-INF/drop-db.sql"/>
+            <property name="jakarta.persistence.sql-load-script-source" value="/META-INF/data.sql"/>
+            <property name="hibernate.id.db_structure_naming_strategy" value="legacy" />
+            <!-- ensure backward compatibility -->
+            <property name="hibernate.type.preferred_duration_jdbc_type" value="BIGINT" />
+            <property name="hibernate.type.preferred_instant_jdbc_type" value="TIMESTAMP" />
+
+        </properties>
+    </persistence-unit>
+    <!-- Persistence unit for PostgreSQL -->
+    <persistence-unit name="com.baeldung.hibernate.entitymanager.game_player_postgresql">
+        <description>EntityManager getReference persistence unit</description>
+        <class>com.baeldung.hibernate.entitymanager.getreference.Game</class>
+        <class>com.baeldung.hibernate.entitymanager.getreference.Player</class>
+        <exclude-unlisted-classes>true</exclude-unlisted-classes>
+        <properties>
+            <!-- even if we set exclude-unlisted-classes=true, strangely it's not enough to exclude defined hbm files in hibernate.cfg.xml.
+            So, some entities out of the scope unwillingly managed by our persistence unit. In order to prevent this, we disable autodetection
+            of the hbm files completely. When we set this property, hibernate ignores the exclude-unlisted-classes property. -->
+            <property name="hibernate.archive.autodetection" value=""/>
+
+            <property name="hibernate.jpa.compliance.proxy" value="false"/>
+
+            <property name="hibernate.hbm2ddl.auto" value="update"/>
+            <property name="hibernate.show_sql" value="true"/>
+            <property name="hibernate.generate_statistics" value="false"/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/>
+            <property name="jakarta.persistence.jdbc.driver" value="org.postgresql.Driver"/>
+            <property name="jakarta.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/postgres"/>
+            <property name="jakarta.persistence.jdbc.user" value="postgres"/>
+            <property name="jakarta.persistence.jdbc.password" value=""/>
+
+            <property name="jakarta.persistence.schema-generation.database.action" value="drop-and-create"/>
+            <property name="jakarta.persistence.schema-generation.create-script-source" value="/META-INF/create-db.sql"/>
+            <property name="jakarta.persistence.schema-generation.drop-script-source" value="/META-INF/drop-db.sql"/>
+            <property name="jakarta.persistence.sql-load-script-source" value="/META-INF/data.sql"/>
+            <property name="hibernate.id.db_structure_naming_strategy" value="legacy" />
+            <!-- ensure backward compatibility -->
+            <property name="hibernate.type.preferred_duration_jdbc_type" value="BIGINT" />
+            <property name="hibernate.type.preferred_instant_jdbc_type" value="TIMESTAMP" />
+
+        </properties>
+    </persistence-unit>
+
+    <persistence-unit name="com.baeldung.hibernate.serializable.h2_persistence_unit">
+        <description>EntityManager serializable persistence unit</description>
+        <class>com.baeldung.hibernate.serializable.Email</class>
+        <class>com.baeldung.hibernate.serializable.Account</class>
+        <class>com.baeldung.hibernate.serializable.User</class>
+        <class>com.baeldung.hibernate.serializable.UserId</class>
+        <exclude-unlisted-classes>true</exclude-unlisted-classes>
+        <properties>
+            <property name="hibernate.hbm2ddl.auto" value="update"/>
+            <property name="hibernate.show_sql" value="true"/>
+            <property name="hibernate.generate_statistics" value="false"/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
+            <property name="jakarta.persistence.jdbc.driver" value="org.h2.Driver"/>
+            <property name="jakarta.persistence.jdbc.url" value="jdbc:h2:mem:db2;DB_CLOSE_DELAY=-1"/>
+            <property name="jakarta.persistence.jdbc.user" value="sa"/>
+            <property name="jakarta.persistence.jdbc.password" value=""/>
+            <property name="hibernate.id.db_structure_naming_strategy" value="legacy" />
+            <!-- ensure backward compatibility -->
+            <property name="hibernate.type.preferred_duration_jdbc_type" value="BIGINT" />
+            <property name="hibernate.type.preferred_instant_jdbc_type" value="TIMESTAMP" />
+
+            <property name="hibernate.globally_quoted_identifiers" value="true"/>
+        </properties>
+    </persistence-unit>
+
     <persistence-unit name="com.baeldung.contextvsunit.h2_persistence_unit" transaction-type="RESOURCE_LOCAL">
         <description>EntityManager serializable persistence unit</description>
         <class>com.baeldung.contextvsunit.entity.Product</class>
@@ -18,5 +140,6 @@
             <property name="jakarta.persistence.jdbc.password" value=""/>
         </properties>
     </persistence-unit>
+</persistence>
+
 
-</persistence> 
\ No newline at end of file