H2

External

• http://www.h2database.com/html/main.html

Internal

• Databases
• Spring H2 Support

Concepts

• H2 Data Types

H2 URLs

Remote:

jdbc:h2:tcp://{host::localhost}[:{port::9092}]/{database::default}[;<;,user={user:param},password={password:param},{:identifier}={:param}>]

In-memory:

jdbc:h2:mem:{database::default}?[;<;,{:identifier}={:param}>]

Embedded:

jdbc:h2:!(tcp://)[file:]{path}[;<;,user={user:param},password={password:param},{:identifier}={:param}>]

Installation

cd $RUNTIME_DIR
unzip .../h2-2017-06-10.zip
mv h2 h2-2017-06-10
ln -s ./h2-2017-06-10 h2

Accessing an H2 Instance Embedded within a Different JVM

By default, the H2 instance is only accessible from the same address space. However, it can be made accessible remotely, over the network, if a org.h2.tools.Server is started in the same JVM:

org.h2.tools.Server server = org.h2.tools.Server.createTcpServer().start();

Once the H2 TCP server is up and running, the instance can be accessed at:

jdbc:h2:tcp://localhost/mem:default;DB_CLOSE_DELAY=-1

The "DB_CLOSE_DELAY=-1" is important, because by default, closing the last connection to a database closes the database. For an in-memory database, this means the content is lost. To keep the database open, add ;DB_CLOSE_DELAY=-1 to the database URL.

Operations

Run Database and H2 Console

cd $RUNTIME_DIR/h2/bin
./h2.sh

This will start a "test" database and make H2 console available on port 8082: http://localhost:8082

The "test" database will be available as "jdbc:h2:tcp://localhost/~/test", authenticating with a "sa" user and an empty password ("").

H2 DDL Operations

H2 DDL Operations

H2 DML Operations

H2 DML Operations