Database Module

This module contains methods to list and open databases, explicitly apply available index structures, or get information on the database structure. All functions are introduced with the db: prefix.

db:system

Signatures	db:system() as xs:string
Summary	Lists information on the database system.
Rules	This function returns a simple string with general information on the database system, such as the database path and current database settings.

db:list

Signatures	db:list() as xs:string*
Summary	Lists all databases.
Rules	This function returns a xs:string sequence with the names of all databases.

db:open

Signatures	db:open($name as xs:string) as document-node()
Summary	Retrieves documents from a database.
Rules	This function opens the documents of the database specified by $name. The name of the database may be extended by a collection path.
Examples	The expression db:open("docs") returns all documents from the database named docs. The expression db:open("docs/one") returns all documents from the database named docs in the subpath one.
Errors	[BASX0003] is raised if the database is not found.

db:open-pre

Signatures	db:open-pre($name as xs:string, $pre as xs:integer) as node()
Summary	Returns a specific database node.
Rules	This function opens the database specified by $name and returns the node with the pre value specified by $pre.
Examples	The expression db:open-pre("docs", 0) returns the first database node from the database named docs.
Errors	[BASX0004] is raised if the specified $pre value does not exist in the database.

db:open-id

Signatures	db:open-id($name as xs:string, $id as xs:integer) as node()
Summary	Returns a specific database node.
Rules	This function opens the database specified by $name and returns the node with the id value specified by $id. In contrast to the pre value, the id will remain valid after update operations.
Errors	[BASX0004] is raised if the specified $id does not exist in the database.

db:node-pre

Signatures	db:node-pre($nodes as node()*) as xs:integer*
Summary	Returns the pre values of database nodes.
Rules	This function returns the pre values of all database nodes specified by $nodes. pre values are direct, internal pointers to database nodes, which might be changed by updates.
Examples	The expression db:node-pre(doc("input")) returns 0 if the database input contains a single document.

db:node-pre

Signatures	db:node-pre($nodes as node()*) as xs:integer*
Summary	Returns the id values of database nodes.
Rules	This function returns the id values of all database nodes specified by $nodes. id values are pointers to database nodes, which are not changed by updates.

db:text

Signatures	db:text($string as item()) as text()*
Summary	Returns results from a text index request.
Rules	This function accesses the text index and returns all text nodes that have $string as string value.
Examples	The expression db:text("QUERY") returns all text nodes of the currently opened database that match the string QUERY. The expression db:open("DB")/db:text("QUERY")/.. returns the parents of all text nodes of the database DB that match the string QUERY.
Errors	[BASX0001] is raised if the index is not available. [BASX0002] is raised if the context item does not represent a database node.

db:attribute

Signatures	db:attribute($string as item()) as attribute()* db:attribute($string as item(), $name as xs:string) as attribute()*
Summary	Returns results from a attribute index request.
Rules	This function accesses the attribute index and returns all attribute nodes that have $string as string value. If $name is specified, the resulting attribute nodes are filtered by their attribute name.
Examples	The expression db:open("DB")/db:attribute("QUERY", "id")/.. returns the parents of all attribute nodes of the database DB that have QUERY as string value.
Errors	[BASX0001] is raised if the index is not available. [BASX0002] is raised if the context item does not represent a database node.

db:fulltext

Signatures	db:fulltext($text as xs:string) as text()
Summary	Returns results from a full-text index request.
Rules	This function accesses the full-text index and returns all text nodes that contain the string $text. The index full-text options are used for searching, i.e., if the index terms were stemmed, the search string will be stemmed as well.
Examples	The expression db:fulltext("QUERY") returns all text nodes of the currently opened database that contain the string QUERY.
Errors	[BASX0001] is raised if the index is not available. [BASX0002] is raised if the context item does not represent a database node.

db:info

Signatures	db:info() as xs:string db:info($type as xs:string) as xs:string
Summary	Returns database information.
Rules	This function returns information on the database that is referenced by the current context item. If $type is specified, the funnction returns information on a database index. It must be one of the values TEXT, ATTRIBUTE, FULLTEXT, PATH, TAG, or ATTNAME.
Errors	[BASX0001] is raised if the specified index is not available. [BASX0002] is raised if the context item does not represent a database node.