Database Module

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Revision as of 22:52, 12 December 2010 by Michael (talk | contribs) (→‎db:text-index: link)
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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 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 Returns 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:text-index

Signatures db:text-index($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.
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-index

Signatures db:attribute-index($string as item()) as attribute()*
db:attribute-index($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.
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-index

Signatures db:fulltext-index($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 $text.
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
Summary Returns database information.
Rules This function returns information on the database that is referenced by the current context item.
Errors [BASX0002] is raised if the context item does not represent a database node.

db:index-info

Signatures db:index-info($type as xs:string) as xs:string
Summary Returns database index information.
Rules This function returns information on an index of the database that is referenced by the current context item.
$type 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.