Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Driver Ask Question. Asked 11 years, 2 months ago. Active 5 months ago. Viewed 90k times. CODE: import java. Ashton Wilkins Ashton Wilkins 1 1 gold badge 3 3 silver badges 3 3 bronze badges. How did you add the Jar to your classpath? Could you please format your code properly - select the code and use the 5th button Code Sample on the editing toolbar while in editing mode.
How are you running your code? Inside Eclipse or from command line? How did you add h2. How did you check for the existence of h2. I then logged out and logged in, checked, and it's there. Show 1 more comment. Active Oldest Votes. Latest version is available here: h2database.
Add a comment. I had to downgrade from 1. Driver Solved it by removing the scope from my pom. How did you do that exactly?
Please show the obtained output. Like this: java -cp h2. Pascal Thivent Pascal Thivent k gold badges silver badges bronze badges. Xianhong Xu Xianhong Xu 99 1 1 silver badge 4 4 bronze badges. If you use Gradle change dependency in build.
Sanchez Sanchez 41 5 5 bronze badges. Connectivity Troubleshooting If you get problems connecting to the database, please remember : Press the ping button in the connection dialog to make sure the host and port are reachable. Enable Remote connections as they are not always enabled by default. This may require configuration changes.
Windows Firewall may block the communication. You may need to reconfigure or disable it. Check the driver version is compatible with the database software. Please inform us in this case. Tomcat uses multiple threads and multiple classloaders. It is a good idea to open the database when the web application starts, and close it when the web application stops. If using multiple applications, only one any of them needs to do that. In the application, an idea is to use one connection per Session, or even one connection per request action.
Those connections should be closed after use if possible but it's not that bad if they don't get closed. For details on how to access the database, see the file DbStarter. If you want to use this connection within your servlet, you can access as follows:.
DbStarter can also start the TCP server, however this is disabled by default. To enable it, use the parameter db. Here is the complete list of options. When the web application is stopped, the database connection will be closed automatically. The H2 Console is a standalone application and includes its own web server, but it can be used as a servlet as well. Instead, import the data first possibly into a temporary table , create the required indexes if necessary, and then query this table.
A fast way to load or import data sometimes called 'bulk load' from a CSV file is to combine table creation with import. Optionally, the column names and data types can be set when creating the table. The Csv tool can be used in a Java application even when not using a database at all.
The recommended way to upgrade from one version of the database engine to the next version is to create a backup of the database in the form of a SQL script using the old engine, and then execute the SQL script using the new engine. The recommended way to backup a database is to create a compressed SQL script file. This will result in a small, human readable, and database version independent backup.
Creating the script will also verify the checksums of the database file. The Script tool is ran as follows:. The backup can be done remotely, however the file will be created on the server side. The built in FTP server could be used to retrieve the file from the server.
The restore can be done remotely, however the file needs to be on the server side. The built in FTP server could be used to copy the file to the server. However, when using the server mode, the references script files need to be available on the server side. If the script was generated by H2 1. However, the contents of this file are not human readable. The resulting backup is transactionally consistent, meaning the consistency and atomicity rules apply.
The Backup tool org. Backup can not be used to create a online backup; the database must not be in use while running this program. Creating a backup by copying the database files while the database is running is not supported, except if the file systems support creating snapshots. With other file systems, it can't be guaranteed that the data is copied in the right order. This database comes with a number of command line tools.
To get more information about a tool, start it with the parameter '-? The tools can also be called from an application by calling the main or another public method. For details, see the Javadoc documentation. The connection setting can also be set as command line parameters.
After connecting, you will get the list of options. The built-in commands don't need to end with a semicolon, but SQL statements are only executed if the line ends with a semicolon ;. This allows to enter multi-line statements:. By default, results are printed as a table. For results with many column, consider using the list mode:.
The steps to connect to a H2 database are:. This can be done by create it using the NetBeans OpenOffice plugin. See also Extensions Development. Otherwise, when trying to write to the file system, the following exception will occur: java. AccessControlException : access denied java.
Example permission tags:. For H2, opening a connection is fast if the database is already open. Still, using a connection pool improves performance if you open and close connections a lot. A simple connection pool is included in H2.
For H2, it is about twice as faster to get a connection from the built-in connection pool than to get one using DriverManager. The build-in connection pool is used as follows:. H2 includes two fulltext search implementations. One is using Apache Lucene, and the other the native implementation stores the index data in special tables in the database. You need to initialize it in each database where you want to use it. Afterwards, you can create a fulltext index for a table using:.
The list of column names comma separated is optional, in this case all columns are indexed. The index is updated in realtime. To search the index, use the following query:. To use the Apache Lucene full text search, you need the Lucene library in the classpath. Apache Lucene 8. To initialize the Lucene fulltext search in a database, call:.
Afterwards, you can create a full text index for a table using:. To drop an index on a table be warned that this will re-index all of the full-text indices for the entire database :. The Lucene fulltext search supports searching in specific column only. Column names must be uppercase except if the original columns are double quoted.
This database supports user-defined variables. Variables start with and can be used wherever expressions or parameters are allowed. Variables are not persisted and session scoped, that means only visible from within the session in which they are defined. A value is usually assigned using the SET command:. Variables that are not set evaluate to NULL. The data type of a user-defined variable is the data type of the value assigned to it, that means it is not necessary or possible to declare variable names before using them.
There are no restrictions on the assigned values; large objects LOBs are supported as well. Rolling back a transaction does not affect the value of a user-defined variable. ISO style datetime formats with T instead of space between date and time parts are also supported. That means if you store the value ' ' in one time zone, then change time zone of the session you will also get ' ', the value will not be adjusted to the new time zone, therefore its absolute value in UTC may be different.
It that case this name will be converted into time zone offset. Names of time zones are not stored. The destroy-method will help prevent exceptions on hot-redeployment or when restarting the server. The standard H2 jar can be dropped in as a bundle in an OSGi container. Any other standard property will be rejected. Non-standard properties will be passed on to H2 in the connection URL. Management over JMX is supported, but not enabled by default.
Various tools support JMX, one such tool is the jconsole. When opening the jconsole , connect to the process where the database is open when using the server mode, you need to connect to the server process. Then go to the MBeans section. Under org. The object name of the entry is the database short name, plus the path each colon is replaced with an underscore character.
To enable JMX, you may need to set the system properties com.
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