Hsql database file

Creating New Database Closing old ResultSet when Statement is reused Automatic Shutdown Validity Check Property Reference to Columns Names String Size Declaration Type Enforcement in Comparison and Assignment Foreign Key Triggered Data Change Concatenation with NULL Truncation or Rounding in Type Conversion Support for NaN values Sort order of NULL values String Comparison with Padding Default Locale Language Collation Case-Insensitive Varchar columns Lowercase column identifiers in ResultSet Storage of Live Java Objects Names of System Indexes Used for Constraints DB2 Style Syntax Oracle Style Syntax Default Table Type Transaction Control Mode Default Isolation Level for Sessions Transaction Rollback in Deadlock Transaction Rollback on Interrupt Time Zone and Interval Types Opening Database as Read Only Opening Database Without Modifying the Files Huge database files and tables Event Logging SQL Logging Temporary Result Rows in Memory Active Oldest Votes.

Improve this answer. In case anyone lands here and is looking for a way to get the. I paraphrase some of the more relevant information: The script file contains the definition of tables and other database objects, plus the data for non-cached tables. Perception Perception Please correct. There is no testdb. Together, all his files make up the database.

I was pointing him to the file that would contain actual data, as indicated in his question. His data is in script and log files and will not go into the data file because he has only memory tables. Sign up or log in Sign up using Google.

Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog.

Podcast Helping communities build their own LTE networks. Podcast Making Agile work for data science. The user can delete these testdb. A res: catalog consists of the files for a small, read-only database that can be stored inside a Java resource such as a ZIP or JAR archive and distributed as part of a Java application program.

In general, JDBC is used for all access to databases. This is done by making a connection to the database, then using various methods of the java. Connection object that is returned to access the data. For example, if the file: database name is "testdb" and its files are located in the same directory as where the command to run your application was issued, the following code is used for the connection:. The database file path format can be specified using forward slashes in Windows hosts as well as Linux hosts.

So relative paths or paths that refer to the same directory on the same drive can be identical. When using relative paths, these paths will be taken relative to the directory in which the shell command to start the Java Virtual Machine was executed.

Paths and database names for file databases are treated as case-sensitive when the database is created or the first connection is made to the database. But if a second connection is made to an open database, using a path and name that differs only in case, then the connection is made to the existing open database. This measure is necessary because in Windows the two paths are equivalent.

A mem: database is specified by the mem: protocol. For mem: databases, the path is simply a name. Several mem: databases can exist at the same time and distinguished by their names. In the example below, the database is called "mymemdb":. A res: database, is specified by the res: protocol.

A Java resource is stored in a compressed format and is decompressed in memory when it is used. For this reason, a res: database should not contain large amounts of data and is always read-only. The first time in-process connection is made to a database, some general data structures are initialised and a helper thread is started.

After this, creation of connections and calls to JDBC methods of the connections execute as if they are part of the Java application that is making the calls. Note that only one Java process at a time can make in-process connections to a given file: database. However, if the file: database has been made read-only, or if connections are made to a res: database, then it is possible to make in-process connections from multiple Java processes.

For most applications, in-process access is faster, as the data is not converted and sent over the network. The main drawback is that it is not possible by default to connect to the database from outside your application. As a result you cannot check the contents of the database with external tools such as Database Manager while your application is running. Server modes provide the maximum accessibility.

The database engine runs in a JVM and opens one or more in-process catalogs. It listens for connections from programs on the same computer or other computers on the network. It translates these connections into in-process connections to the databases. Several different programs can connect to the server and retrieve or update information. In most server modes, the server can serve an unlimited number of databases that are specified at the time of running the server, or optionally, as a connection request is received.

A Sever mode is also the preferred mode of running the database during development. It allows you to query the database from a separate database access utility while your application is running. There are three server modes, based on the protocol used for communications between the client and server.

They are briefly discussed below. This is the preferred way of running a database server and the fastest one. A proprietary communications protocol is used for this mode. A command similar to those used for running tools and described above is used for running the server. The following example of the command for starting the server starts the server with one default database with files named "mydb. The public name hides the file names from users.

The command line argument --help can be used to get a list of available arguments. Connections are made using an hsql: URL. This method of access is used when the computer hosting the database server is restricted to the HTTP protocol. The only reason for using this method of access is restrictions imposed by firewalls on the client or server machines and it should not be used where there are no such restrictions.

The server can also act as a small general-purpose web server for static pages. Connections are made using an httpl: URL. This method of access also uses the HTTP protocol. It is used when a servlet engine or application server such as Tomcat or Resin provides access to the database. The Servlet Mode cannot be started independently from the servlet engine. The database file path is specified using an application server property. They do not provide a web front end to the database.

The Servlet mode can serve multiple databases. Please note that you do not normally use this mode if you are using the database engine in an application server. In this situation, connections to a catalog are usually made in-process , or using the hsql: protocol to an HSQL Server.

A common example is connection to the default port used for the hsql: protocol on the same machine:. Note in the above connection URL, there is no mention of the database file, as this was specified when running the server. Instead, the public name defined for dbname. When a HyperSQL server is run, network access should be adequately protected.