Difference between revisions of "Database Server"

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</code>
 
</code>
  
===Create an another database / switch between databases===
+
===Create a new database / switch between databases===
Now we will create an another database. You can get the xml document from here [http://phobos101.inf.uni-konstanz.de/basex/demo].
+
Now we will create another database. You can find the example document here: [http://phobos101.inf.uni-konstanz.de/basex/demo].
:<code>
 
> create db xmark xmark.xml
 
</code>
 
 
 
To set the new database xmark as the context (the active, opened database), use:
 
:<code>
 
> open xmark
 
</code>
 
 
 
Now you can simply type your xquery:
 
:<code>
 
> xquery //people/person/name
 
</code>
 
  
If you want to query the factbook database you can access it by explicitly naming it with the doc()-function.
+
* Create the new database, named 'xmark'.
:<code>
+
<code>
> xquery doc("factbook")//country
+
: > create db xmark xmark.xml
 
</code>
 
</code>
  
If you want to set the factbook database as the context, you can use:
+
* Set the new database xmark as the context:
:<code>
+
<code>
> open factbook
+
: > open xmark
 
</code>
 
</code>
  
To see which database is opened, use:
+
* Now you can easily execute queries on your new database:
:<code>
+
<code>
> show databases
+
: > xquery //people/person/name
 
</code>
 
</code>
  

Revision as of 14:56, 10 January 2011

This step by step tutorial shows you how to run BaseX in client-server mode from a terminal. You can copy & paste the commands to get it running on your machine. After you finished this tutorial, you will be familiar with the basic BaseX commands.

Requirements

Java 1.6 is required to run newer versions of BaseX. If you need help installing Java please visit java.com. We assume that you are familiar with a shell at a basic level.

Download

Download the basex.jar. In scope of this tutorial we assume that the basex.jar file is located in /basex.

Starting the Server

  • Navigate to the location of basex.jar (> cd /basex).
  • You can either start the server in interaction mode if you add the -i flag. This allows you to further interact with the server during runtime (add databases or users, ...).

> java -cp BaseX.jar org.basex.BaseXServer -i

Or the server can be started alternatively without the -i flag. Note, that you have to restart the server to execute further commands from this shell.

> java -cp BaseX.jar org.basex.BaseXServer

  • A default admin user is created (you can change the password with the PASSWORD command):
Username: admin
Password: admin
  • Once the server has successfully started you see the following lines:
BaseXServer [Server]
Server was started.

Starting the Client

  • Open a new terminal window, make sure you are in the right directory (/basex).
  • Execute the following to start the client:

> java -cp BaseX.jar org.basex.BaseXClient

  • If you haven't changed the password with the server, you can login as default user (admin/admin).

First Operations

To get familiar with BaseX we suggest to execute the following basic operations.

Create a database

  • To create a database you need an XML document, e.g. factbook.xml.
  • Save this document to the /basex directory.
  • On the client terminal run:

> create db factbook factbook.xml

factbook - is the name of the database
factbook.xml - is the xml file, which is used to create the database

If everything works you see the following lines:

Database 'factbook' created in 1950.83 ms.
Where is the database stored?

Databases are stored in the BaseXData directory which is located in your home folder. Depending on your operating system the location of your home folder varies. For example, on a mac it's /Users/John, if your name is John.

Execute a query

The xquery command lets you run a query.

  • For example, this query returns all country nodes in the currently opened database.

> xquery //country

  • You can also run queries in files:

> run /Users/John/query.xq

Create a new database / switch between databases

Now we will create another database. You can find the example document here: [1].

  • Create the new database, named 'xmark'.

> create db xmark xmark.xml

  • Set the new database xmark as the context:

> open xmark

  • Now you can easily execute queries on your new database:

> xquery //people/person/name

Close or delete a database

If you want to close the opened database, simply type:

> close

If you want to delete the xmark database, use:

> drop db xmark

Create a collection

What is a collection? With BaseX you can group documents into one logical collection. A collection is a database that contains two or more documents. You can put any type of XML documents into the collection, regardless of their structure.

Now we will add the xmark.xml document to the factbook database, and thus create a collection. The collection will keep the name factbook.

First make sure factbook is opened:

> open factbook

Now add the xmark.xml document:

> add xmark.xml

Delete a document from a collection

Deleting a document from a collection is very easy, just type:

> delete xmark.xml

N.B. The collection has to be the context i.e. the database which contains the document has to be opened.

Delete a collection

Deleting a collection is the same as deleting a database. If you want to delete the collection factbook, type:

> drop factbook

Getting information about the server

To see all databases on the server, type:

> list

To see which database is currently opened, type:

> show databases

To see the general information of the opened database, type:

> info

To see the users in BaseX, type:

> show users

Backup and Restore

To backup your database, type:

> backup factbook

To restore your database, type:

> restore factbook

Where is the backup-file stored?

The backup-file is stored in the BaseXData directory, which is in your home directory. The file is named factbook-timestamp.zip (db_name-timestamp.zip). To restore the database the file with the newest timestamp is taken.

See also

BaseX Standalone, BaseX GUI, Getting Started Guide, Advanced User Portal