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Revision as of 23:09, 18 October 2011 by Jens Erat (talk | contribs) (Valid database names.)
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This page is part of the Getting Started Section.

In BaseX, a single database contains an arbitrary number of resources. By default, all resources have been XML documents. Since Version 7.0, however, raw files (binaries) can be stored as well. Valid database names are defined by [_-a-zA-Z0-9]+.

Create/Drop Database

New databases can either be created in the GUI, on command line, or using any of our APIs. XML documents can be specified along with the create operation, which will be added to the database in a bulk operation:

  • Console: enter basex -c "CREATE DB dbname /path/to/resources"
  • GUI: Go to DatabaseNew, press Browse to choose an initial file or directory, and press OK

Various parsers can be chosen to influence the database creation, or to convert different formats to XML,

Existing databases can eventually be dropped again:

  • Console: enter basex -c "DROP DB dbname".
  • GUI: Go to DatabaseManage and choose the database to be dropped

Manage Resources

Once you have created a database, additional commands exist to modify its contents:

  • XML documents can be added with the ADD command.
  • Raw files are added with STORE.
  • Any resource can be replaced with another using the REPLACE command.
  • Any resources can be deleted with the DELETE command.

To speed up the insertion of new documents in bulk operations, you can turn the AUTOFLUSH option off.

The following commands create an empty database, add two resources and finally delete them again:

CREATE DB example
ADD example.xml
ADD ...
STORE TO images/ 123.jpg

You may as well use the BaseX-specific XQuery Database Functions to add, replace and delete XML documents:

for $file in file:list("/path/to/xml/documents")
return db:add("database", $file)

Last but not least, XML documents can also be added via the GUI and the Database menu.

Access Resources

The stored resources can be accessed in different ways:

XML Documents

Various XQuery functions exist to access the XML documents in databases and other locations:

  • db:open("dbname", "path/to/docs"): (only) returns documents that are found in the specified database.
  • collection("path/to/docs"): returns the documents that are either found in the database specified in the argument, or at the specified location (file path or URL).
  • doc("path/to/document.xml"): returns a single document found at the specified location (file path or URL). If a database already exists for the addressed resource, it is opened instead.

Raw Files

  • The RETRIEVE command returns raw files without modifications.
  • The XQuery function db:retrieve("dbname", "path/to/docs") returns raw files in their Base64 representation. By choosing "method=raw" as Serialization Option, the data is returned in its raw form:
declare option output:method "raw";
db:retrieve('multimedia', 'sample.avi')