Connect to H2 database using IntelliJ database client
GrailsIntellij IdeaH2Grails Problem Overview
My Grails app uses a h2 database in dev mode (the default behaviour for Grails apps). The DB connection settings in DataSource.groovy
are
dataSource {
pooled = true
jmxExport = true
driverClassName = "org.h2.Driver"
username = "sa"
password = ""
dbCreate = "create-drop" // one of 'create', 'create-drop', 'update', 'validate', ''
url = "jdbc:h2:mem:devDb;MVCC=TRUE;LOCK_TIMEOUT=10000;DB_CLOSE_ON_EXIT=FALSE"
}
I'm trying to setup a connection for this database using IntelliJ IDEA's database client tools. I start off creating the connection like so
Then in the following dialog, I enter the JDBC URL
And choose all available databases on the "Schemas & Tables" tab.
The "Test Connection" button indicates success, but as you can see from the red circle, no tables are found. It seems like I've correctly setup a connection to the h2 server, but not the schema itself.
BTW, I try to setup this connection once the app is running, so I'm sure that the schema/tables do actually exist.
Grails Solutions
Solution 1 - Grails
Your configuration is for an h2:mem
database. Memory Databases have no tables upon connecting to them, and any & all tables are lost when all the connections are closed. Furthermore, a (named) in memory database is unique to the JVM process that opens it. From the H2 documentation:
> Sometimes multiple connections to the same in-memory database are required. In this case, the database URL must include a name. Example: jdbc:h2:mem:db1. Accessing the same database using this URL only works within the same virtual machine and class loader environment. (Emphasis added)
This means IDEA will create a unique devDb
in its JVM (and classloader) space and your application will create a unique devDb
in its JVM (and classloader) space. You can not connect to an in memory database from an external JVM process.
If you want to connect both your application and IntelliJ IDEA (or any other DB tool) to an H2 database at the same time, you will need to either
- use an embedded database (that writes to a file) in your application and use
Mixed Mode
to allow IntelliJ IDEA (and/or other database tools) to connect to it - use a server mode database
See http://www.h2database.com/html/features.html#connection_modes for more information.
Solution 2 - Grails
This article has a great write up on how to set up the IntelliJ database client to connect to an H2 in-memory database if you happen to be using Spring Boot: http://web.archive.org/web/20160513065923/http://blog.techdev.de/querying-the-embedded-h2-database-of-a-spring-boot-application/
Basically, you wrap the in-memory database with a tcp server, then you have an access point to connect with a sql client via remote access.
Solution 3 - Grails
During development you can use grails h2 dbconsole
Solution 4 - Grails
Try to open http://localhost:8080/dbconsole and fill your jdbc url
Solution 5 - Grails
Let's imagine you've already created entities (Users, Addresses)
Step 1. In application.yml file add H2 properties.
server:
port: 8080
spring:
datasource:
url: jdbc:h2:~/data/parserpalce (for Mac OS)
username: sa
password: password
driver-class-name: org.h2.Driver
jpa:
database-platform: org.hibernate.dialect.H2Dialect
hibernate:
ddl-auto: update
h2:
console:
enabled: true
Step 2. Add H2 Database client
Step 3. Configure H2 database client properties based on your application.yml properties.
Step 4. Run the application.
Step 5. Check if tables(Users, Addresses) are created.
Or you can use H2 console for it in browser: http://localhost:8080/h2-console
P.S. Do not forget to paste appropriate values in fields!