I am trying to use the H2 database from a Java application.
I created the database and its tables through the H2 Console and then I try to connect from Java using
Connection con = DriverManager.getConnection("jdbc:h2:~/dbname", "username", "password");
However I receive the following error:
Exception in thread "main" org.h2.jdbc.JdbcSQLException: Database may be already in use: "Locked by another process". Possible solutions: close all other connection(s); use the server mode [90020-161]
I tried to delete the dbname.lock.db
file but it is automatically re-created.
How can I unlock the database to use it from my Java program?
If you are running same app into multiple ports where app uses single database (h2), then add AUTO_SERVER=TRUE
in the url as follows:
jdbc:h2:file:C:/simple-commerce/price;DB_CLOSE_ON_EXIT=FALSE;AUTO_RECONNECT=TRUE;AUTO_SERVER=TRUE
You can also visit the "Preferences" tab from the H2 Console and shutdown all active sessions by pressing the shutdown button.
I had the same problem. in Intellj, when i want to use h2 database when my program was running i got the same error. For solve this problem i changed the connection url from
spring.datasource.url=jdbc:h2:file:~/ipinbarbot
to:
spring.datasource.url=jdbc:h2:~/ipinbarbot;DB_CLOSE_ON_EXIT=FALSE;AUTO_SERVER=TRUE
And then my problem gone away. now i can connect to "ipinbarbot" database when my program is. If you use Hibernate, also don't forget to have:
spring.jpa.hibernate.ddl-auto = update
goodluck
For InteliJ: right lick on your database in the database view and choose "Disconnect".
You can also delete file of the h2 file database and problem will disappear.
jdbc:h2:~/dbname means that file h2 database with name db name will be created in the user home directory(~/ means user home directory, I hope you work on Linux).
In my local machine its present in: /home/jack/dbname.mv.db I don't know why file has a name dbname.mv.db instead a dbname. May be its a h2 default settings. I remove this file:
rm ~/dbname.mv.db
OR:
cd ~/
rm dbname.mv.db
Database dbname will be removed with all data. After new data base init all will be ok.
Simple step: Go to the task manager and kill the java process
then start your apllication
I got clue from Saman Salehi above. My usecase: Preparing REST application for client-side load balancing(running two JVM instances of REST). Here my MVC application will call this REST application that has ActiveMQ backend for DATA. I had the problem when I ran two instances of REST application in eclipse and trying to run both instances at the same time with the following configuration
spring.datasource.url=jdbc:h2:file:./Database;
spring.jpa.properties.hibernate.hbm2ddl.auto=update
After adding DB_CLOSE_ON_EXIT=FALSE;AUTO_SERVER=TRUE
spring.datasource.url=jdbc:h2:file:./Database;DB_CLOSE_ON_EXIT=FALSE;AUTO_SERVER=TRUE
Both instances are running and showing in Eureka dasboard.
Don't close the database when the VM exits : jdbc:h2:;DB_CLOSE_ON_EXIT=FALSE
Multiple processes can access the same database without having to start the server manually ;AUTO_SERVER=TRUE
Further reading: http://www.h2database.com/html/features.html
Ran into a similar issue the solution for me was to run fuser -k 'filename.db'
on the file that had a lock associated with it.
Hope this helps!
answer for this question => Exception in thread "main" org.h2.jdbc.JdbcSQLException: Database may be already in use: "Locked by another process". Possible solutions: close all other connection(s); use the server mode [90020-161]
close all tab from your browser where open h2 database also Exit h2 engine from your pc
I'm using h2db with a test T24 tafj application, I had the same problem but I managed to resolve it by identifying the application that is running h2 (launched when I attempted to setup a database connection).
ps aux|grep java
will give output as:
sysadmin 22755 3.2 0.1 5189724 64008 pts/3 Sl 08:28 0:00 /usr/java/default/bin/java -server -Xmx2048M -XX:MaxPermSize=256M -cp h2-1.3.175.jar:/r14tafj/TAFJ/dbscripts/h2/TAFJFunctions.jar org.h2.tools.Server -tcp -tcpAllowOthers -baseDir /r14tafj/t24/data
now kill this with its process id:
kill -9 22755
and at last remove the lock file:
rm -f dbname.lock.db
I ran into similar problems running with ORMLite from a web application. I initially got stuck on the syntax to use server mode in the url. The answers above helped with that. Then I had the similar user/password error which was easier to figure out. I did not have to shut anything down or erase any files. The following code worked:
protected ConnectionSource getConnectionSource() throws SQLException {
String databaseUrl = "jdbc:h2:tcp://localhost/~/test";
return new JdbcConnectionSource(databaseUrl,"sa","sa");
}
To use H2 in server mode on wildfly, I Modifed connection-url in standalone.xml
<datasource jndi-name="java:jboss/datasources/ExampleDS" pool- name="ExampleDS" enabled="true" use-java-context="true">
<connection-url>jdbc:h2:tcp://localhost/~/test</connection-url>
…
</datasource>
Source: Stackoverflow.com