Difference between revisions of "Database Module"

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=Conventions=
 
=Conventions=
  
All functions in this module are assigned to the <code><nowiki>http://basex.org/modules/db</nowiki></code> namespace, which is statically bound to the {{Code|db}} prefix.<br/>
+
All functions and errors in this module are assigned to the <code><nowiki>http://basex.org/modules/db</nowiki></code> namespace, which is statically bound to the {{Code|db}} prefix.<br/>
All errors are assigned to the <code><nowiki>http://basex.org/errors</nowiki></code> namespace, which is statically bound to the {{Code|bxerr}} prefix.
 
  
 
==Database Nodes==
 
==Database Nodes==
  
Database nodes are XML nodes which are either stored in a persistent database or part of a so-called ''database fragment''. All XML fragments can be converted to database fragments by e. g. applying the [[XQuery_Update#transform|transform]] expression on an XML fragment:
+
Database nodes are XML nodes which are either stored in a persistent database, or which are a node of a main-memory database representation. XML fragments can be converted to a main-memory database by e. g. applying the [[XQuery_Update#update|update]] or [[XQuery_Update#transform|transform]] expression on a node:
  
 
<pre class="brush:xquery">
 
<pre class="brush:xquery">
copy $c := element hello { 'world' } modify () return $c
+
db:node-id(element hello { 'world' } update {})
 
</pre>
 
</pre>
  
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|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Returns information on the database system, such as the database path and current database settings. The output is similar to the [[Commands#INFO|INFO]] command.
+
|Returns general information on the database system the current values of all global and local [[Options]]. The {{Command|INFO}} command returns similar output.
 +
|}
 +
 
 +
==db:option==
 +
 
 +
{| width='100%'
 +
|-
 +
| width='120' | '''Signatures'''
 +
|{{Func|db:option|$name as xs:string|xs:string}}
 +
|-
 +
| '''Summary'''
 +
|Returns the current value (string, integer, boolean, map) of a global or local [[Options|Option]] with the specified {{Code|$name}}. The {{Command|GET}} command works similar.
 +
|-
 +
| '''Errors'''
 +
|{{Error|option|#Errors}} the specified option is unknown.
 +
|-
 +
| '''Examples'''
 +
|
 +
* <code>db:option('dbpath')</code> returns the database path string.
 +
* <code>db:option('serializer')</code> returns a map with the current serialization parameters.
 +
* <code>declare option db:chop 'true'; db:option('chop')</code> returns {{Code|true}} (irrespective of the global value).
 
|}
 
|}
  
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|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Returns meta information on the database {{Code|$db}}. The output is similar to the [[Commands#INFO DB|INFO DB]] command.
+
|Returns meta information on the database {{Code|$db}}. The output is similar to the {{Command|INFO DB}} command.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 +
|}
 +
 
 +
==db:property==
 +
 
 +
{| width='100%'
 +
|-
 +
| width='120' | '''Signatures'''
 +
|{{Func|db:property|$db as xs:string, $name as xs:string|xs:anyAtomicType}}
 +
|-
 +
| '''Summary'''
 +
|Returns the value (string, boolean, integer) of a property with the specified {{Code|$name}} in the database {{Code|$db}}. The available properties are the ones returned by [[#db:info|db:info]].
 +
|-
 +
| '''Errors'''
 +
|{{Error|property|#Errors}} the specified property is unknown.
 +
|-
 +
| '''Examples'''
 +
|
 +
* <code>db:property('db', 'size')</code> returns the number of bytes occupied by the database <code>db</code>.
 +
* <code>db:property('xmark', 'textindex')</code> indicates if the <code>xmark</code> database has a text index.
 +
* <code>db:property('discogs', 'uptodate')</code> indicates if the database statistics and index structures of the <code>discogs</code> database are up-to-date.
 
|}
 
|}
  
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| '''Summary'''
 
| '''Summary'''
 
|The result of this function is dependent on the number of arguments:
 
|The result of this function is dependent on the number of arguments:
* Without arguments, the names of all databases are returned.
+
* Without arguments, the names of all databases are returned that are accessible to the current user.
 
* If a database {{Code|$db}} is specified, all documents and raw files of the specified database are returned.
 
* If a database {{Code|$db}} is specified, all documents and raw files of the specified database are returned.
 
* The list of returned resources can be restricted by the {{Code|$path}} argument.
 
* The list of returned resources can be restricted by the {{Code|$path}} argument.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Without arguments, an element is returned for each database:
+
|Without arguments, an element is returned for each database that is accessible to the current user:
 
* An element has a value, which is the name of the database, and several attributes, which contain the number of stored resources, the modification date, the database size on disk (measured in bytes), and a path to the original database input.
 
* An element has a value, which is the name of the database, and several attributes, which contain the number of stored resources, the modification date, the database size on disk (measured in bytes), and a path to the original database input.
 
If a database {{Code|$db}} is specified, an element for each documents and raw file of the specified database is returned:
 
If a database {{Code|$db}} is specified, an element for each documents and raw file of the specified database is returned:
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
 
|
 
|
 
* {{Code|db:list-details("shop")}} returns the names plus additional info on all resources of a database named {{Code|shop}}.
 
* {{Code|db:list-details("shop")}} returns the names plus additional info on all resources of a database named {{Code|shop}}.
 +
|}
 +
 +
==db:dir==
 +
 +
{{Mark|Introduced with Version 9.2:}}
 +
 +
{| width='100%'
 +
|-
 +
| width='120' | '''Signatures'''
 +
|{{Func|db:dir|$db as xs:string, $path as xs:string|element()*}}
 +
|-
 +
| '''Summary'''
 +
|Returns meta data on all directories and resources of the database {{Code|$db}} in the specified directory {{Code|$path}}. Two types of elements are returned:
 +
* {{Code|resource}} represents a resource. The element value is the directory path; content type, modification date, raw flag (which indicates if the resource is binary or XML), and size of the resource are returned as attributes.
 +
* {{Code|dir}} represents a directory. The element value is the directory path; the modification date is returned as attribute.
 +
Please note that directories are not stored in BaseX. Instead, they result implicitly from the paths of stored resources.
 +
|-
 +
| '''Errors'''
 +
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|path|#Errors}} the specified path is invalid.
 +
|-
 +
| '''Examples'''
 +
|
 +
* {{Code|db:dir('shop', 'books')}} returns all entries of the {{Code|books}} directory of a {{Code|shop}} database.
 
|}
 
|}
  
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0009|XQuery Errors#BaseX Errors}} the specified pre value does not exist in the database.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|range|#Errors}} the specified pre value does not exist in the database.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0009|XQuery Errors#BaseX Errors}} the specified id value does not exist in the database.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|range|#Errors}} the specified id value does not exist in the database.
 
|}
 
|}
  
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0001|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
+
|{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0001|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
+
|{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
 
|}
 
|}
  
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0003|#Errors}} the database is not ''persistent'' (stored on disk).<br/>{{Error|FODC0002|XQuery Errors#Functions Errors}} the addressed resource cannot be retrieved.<br/>{{Error|FODC0007|XQuery Errors#Functions Errors}} the specified path is invalid.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|mainmem|#Errors}} the database is not ''persistent'' (stored on disk).
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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* {{Code|db:retrieve("DB", "music/01.mp3")}} returns the specified audio file as raw data.
 
* {{Code|db:retrieve("DB", "music/01.mp3")}} returns the specified audio file as raw data.
 
* <code><nowiki>stream:materialize(db:retrieve("DB", "music/01.mp3"))</nowiki></code> materializes the streamable result in main-memory before returning it.
 
* <code><nowiki>stream:materialize(db:retrieve("DB", "music/01.mp3"))</nowiki></code> materializes the streamable result in main-memory before returning it.
 +
* <code><nowiki>convert:binary-to-string(db:retrieve("DB", "info.txt"), 'UTF-8')</nowiki></code> converts a binary database resource as UTF-8 text and returns a string.
 
|}
 
|}
  
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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==db:text==
 
==db:text==
 +
 +
{{Mark|Updated with Version 9.1}}: Support for multiple string values.
  
 
{| width='100%'
 
{| width='100%'
 
|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:text|$db as xs:string, $string as item()|text()*}}
+
|{{Func|db:text|$db as xs:string, $strings as xs:string*|text()*}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Returns all text nodes of the database {{Code|$db}} that have {{Code|$string}} as their string value and that are stored in the text index.
+
|Returns all text nodes of the database {{Code|$db}} that have one of the specified {{Code|$strings}} as values and that are stored in the text index.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0004|Database Module#Errors}} the index is not available.<br/>
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|no-index|#Errors}} the index is not available.<br/>
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0004|Database Module#Errors}} the index is not available.<br/>
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|no-index|#Errors}} the index is not available.<br/>
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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==db:attribute==
 
==db:attribute==
 +
 +
{{Mark|Updated with Version 9.1}}: Support for multiple string values.
  
 
{| width='100%'
 
{| width='100%'
 
|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:attribute|$db as xs:string, $string as item()|attribute()*}}<br/>{{Func|db:attribute|$db as xs:string, $string as item(), $name as xs:string|attribute()*}}
+
|{{Func|db:attribute|$db as xs:string, $strings as xs:string*|attribute()*}}<br/>{{Func|db:attribute|$db as xs:string, $strings as xs:strings*, $name as xs:string|attribute()*}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Returns all attribute nodes of the database {{Code|$db}} that have {{Code|$string}} as string value and that are stored in the attribute index.<br />If {{Code|$name}} is specified, the resulting attribute nodes are filtered by their attribute name.
+
|Returns all attribute nodes of the database {{Code|$db}} that have one of the specified {{Code|$strings}} as values and that are stored in the attribute index.<br />If {{Code|$name}} is specified, the resulting attribute nodes are filtered by their attribute name.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0004|Database Module#Errors}} the index is not available.<br/>
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|no-index|#Errors}} the index is not available.<br/>
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0004|Database Module#Errors}} the index is not available.<br/>
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|no-index|#Errors}} the index is not available.<br/>
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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==db:token==
 
==db:token==
 +
 +
{{Mark|Updated with Version 9.1}}: Support for multiple string values.
  
 
{| width='100%'
 
{| width='100%'
 
|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:token|$db as xs:string, $token as item()|attribute()*}}<br/>{{Func|db:token|$db as xs:string, $token as item(), $name as xs:string|attribute()*}}
+
|{{Func|db:token|$db as xs:string, $tokens as xs:string*|attribute()*}}<br/>{{Func|db:token|$db as xs:string, $tokens as xs:string*, $name as xs:string|attribute()*}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Returns all attribute nodes of the database {{Code|$db}}, the value of which contains the specified {{Code|$token}}.<br />If {{Code|$name}} is specified, the resulting attribute nodes are filtered by their attribute name.
+
|Returns all attribute nodes of the database {{Code|$db}} the values of which contain one of the specified {{Code|$tokens}}.<br />If {{Code|$name}} is specified, the resulting attribute nodes are filtered by their attribute name.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0004|Database Module#Errors}} the index is not available.<br/>
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|no-index|#Errors}} the index is not available.<br/>
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:create|$db as xs:string|empty-sequence()}}<br/>{{Func|db:create|$db as xs:string, $inputs as item()*|empty-sequence()}}<br/>{{Func|db:create|$db as xs:string, $inputs as item()*, $paths as xs:string*|empty-sequence()}}<br/>{{Func|db:create|$db as xs:string, $inputs as item()*, $paths as xs:string*, $options as map(*)|empty-sequence()}}
+
|{{Func|db:create|$db as xs:string|empty-sequence()}}<br/>{{Func|db:create|$db as xs:string, $inputs as item()*|empty-sequence()}}<br/>{{Func|db:create|$db as xs:string, $inputs as item()*, $paths as xs:string*|empty-sequence()}}<br/>{{Func|db:create|$db as xs:string, $inputs as item()*, $paths as xs:string*, $options as map(*)?|empty-sequence()}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
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** strings can be a URI pointing to a file/directory or an XML string (which is detected by the leading <code>&lt;</code> character)
 
** strings can be a URI pointing to a file/directory or an XML string (which is detected by the leading <code>&lt;</code> character)
 
** a path must be specified if the input is not a file or directory reference
 
** a path must be specified if the input is not a file or directory reference
* The {{Code|$options}} argument can be used to change the indexing behavior:
+
* The parsing and indexing behavior can be controlled via {{Code|$options}}:
** the allowed options are {{Option|ADDCACHE}} and the [[Options#Indexing|indexing]], [[Options#Full-Text|full-text]], [[Options#Parsing|parsing]] and [[Options#XML Parsing|XML parsing]] options, all in lower case.
+
** allowed options are {{Option|ADDCACHE}} and the [[Options#Indexing|indexing]], [[Options#Full-Text Indexing|full-text indexing]], [[Options#Parsing|parsing]] and [[Options#XML Parsing|XML parsing]] options, all in lower case
** parsing options are only applied to string input (XML strings or file/directory references) specified via this command. If you plan to add data in a subsequent step, you need to specify your options along with these commands.
+
** parsing options will only impact string input (URIs, XML strings), because nodes have already been parsed.
 
* An existing database will be overwritten.
 
* An existing database will be overwritten.
 
* Database creation takes place after most other update operations (see [[XQuery Update#Pending Update List|Pending Update List]]). As a consequence, a newly created database cannot be addressed in the same query.
 
* Database creation takes place after most other update operations (see [[XQuery Update#Pending Update List|Pending Update List]]). As a consequence, a newly created database cannot be addressed in the same query.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|FODC0002|XQuery Errors#Functions Errors}} an input points to an unknown resource.<br/>{{Error|FOUP0001|XQuery Errors#Update Errors}} an attribute was specified as input.<br/>{{Error|BXDB0007|#Errors}} a database is opened by another process.<br/>{{Error|BXDB0011|#Errors}} the specified name is not a [[Commands#Valid_Names|valid database name]].<br/>{{Error|BXDB0012|#Errors}} two {{Code|db:create}} statements with the same database name were specified.<br/>{{Error|BXDB0013|#Errors}} the number of specified inputs and paths differs.
+
|{{Error|lock|#Errors}} a database is opened by another process.<br/>{{Error|name|#Errors}} the specified name is not a [[Commands#Valid_Names|valid database name]].<br/>{{Error|conflict|#Errors}} the same database was addressed more than once.<br/>{{Error|args|#Errors}} the number of specified inputs and paths differs.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0007|#Errors}} a database is opened by another process.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|lock|#Errors}} a database is opened by another process.<br/>{{Error|conflict|#Errors}} the same database was addressed more than once.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:add|$db as xs:string, $input as item()|empty-sequence()}}<br/>{{Func|db:add|$db as xs:string, $input as item(), $path as xs:string|empty-sequence()}}<br/>{{Func|db:add|$db as xs:string, $input as item(), $path as xs:string, $options as map(*)|empty-sequence()|empty-sequence()}}
+
|{{Func|db:add|$db as xs:string, $input as item()|empty-sequence()}}<br/>{{Func|db:add|$db as xs:string, $input as item(), $path as xs:string|empty-sequence()}}<br/>{{Func|db:add|$db as xs:string, $input as item(), $path as xs:string, $options as map(*)?|empty-sequence()|empty-sequence()}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
 
|Adds documents specified by {{Code|$input}} to the database {{Code|$db}} with the specified {{Code|$path}}:
 
|Adds documents specified by {{Code|$input}} to the database {{Code|$db}} with the specified {{Code|$path}}:
 
* A document with the same path may occur more than once in a database. If you want to enforce single instances, use [[#db:replace|db:replace]] instead.
 
* A document with the same path may occur more than once in a database. If you want to enforce single instances, use [[#db:replace|db:replace]] instead.
* For more information on the arguments, see [[#db:create|db:create]] (note that the specified options cannot be [[Options#Indexing|indexing]] and [[Options#Full-Text|full-text]] options).
+
* See [[#db:create|db:create]] for more details on the input argument.
 +
* The parsing behavior can be controlled via {{Code|$options}}:
 +
** allowed options are {{Option|ADDCACHE}} and the [[Options#Parsing|parsing]] and [[Options#XML Parsing|XML parsing]] options, all in lower case
 +
** parsing options will only impact string input (URIs, XML strings), because nodes have already been parsed
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|FODC0002|XQuery Errors#Functions Errors}} the input points to an unknown resource.<br/>{{Error|FOUP0001|XQuery Errors#Update Errors}} an attribute was specified as input.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
 
|
 
|
* {{Code|db:add("DB", "/home/dir/doc.xml")}} adds the file {{Code|/home/dir/doc.xml}} to the database {{Code|DB}}.
+
* <code>db:add("DB", "/home/dir/doc.xml")</code> adds the file {{Code|/home/dir/doc.xml}} to the database {{Code|DB}}.
* {{Code|db:add("DB", <a/>, "doc.xml")}} adds a document node to the database {{Code|DB}} under the name {{Code|doc.xml}}.
+
* <code>db:add("DB", <a/>, "doc.xml")</code> adds a document node to the database {{Code|DB}} under the name {{Code|doc.xml}}.
* {{Code|db:add("DB", "/home/dir", "docs/dir")}} adds all documents in {{Code|/home/dir}} to the database {{Code|DB}} under the path {{Code|docs/dir}}.
+
* <code>db:add("DB", "/home/dir", "docs/dir", map { 'addcache': true() })</code> adds all documents in {{Code|/home/dir}} to the database {{Code|DB}} under the path {{Code|docs/dir}}. In order to reduce memory consumption, the files will be cached before being added to the database.
 
|}
 
|}
  
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|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0008|#Errors}} the specified path is invalid.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|path|#Errors}} the specified path is invalid.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
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|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:copy|$db as xs:string, $newname as xs:string|empty-sequence()}}
+
|{{Func|db:copy|$db as xs:string, $name as xs:string|empty-sequence()}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Creates a copy of the database specified by {{Code|$db}} to {{Code|$newname}}.
+
|Creates a copy of the database {{Code|$db}}, which will be called {{Code|$name}}.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0011|XQuery Errors#BaseX Errors}} invalid database name.<br/>{{Error|BXDB0016|XQuery Errors#BaseX Errors}} name of source and target database is equal.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|lock|#Errors}} a database is opened by another process.<br/>{{Error|name|#Errors}} invalid database name.<br/>{{Error|conflict|#Errors}} the same database was addressed more than once.
 
|}
 
|}
  
Line 452: Line 524:
 
|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:alter|$db as xs:string, $newname as xs:string|empty-sequence()}}
+
|{{Func|db:alter|$db as xs:string, $name as xs:string|empty-sequence()}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
|Renames the database specified by {{Code|$db}} to {{Code|$newname}}.
+
|Renames the database {{Code|$db}} to {{Code|$name}}.
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0011|XQuery Errors#BaseX Errors}} invalid database name.<br/>{{Error|BXDB0016|XQuery Errors#BaseX Errors}} name of source and target database is equal.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|lock|#Errors}} a database is opened by another process.<br/>{{Error|name|#Errors}} invalid database name.<br/>{{Error|conflict|#Errors}} the same database was addressed more than once.
 
|}
 
|}
  
Line 472: Line 544:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0011|XQuery Errors#BaseX Errors}} invalid database name.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|name|#Errors}} invalid database name.<br/>{{Error|conflict|#Errors}} the same database was addressed more than once.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 490: Line 562:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} No backup file found.<br/>{{Error|BXDB0011|XQuery Errors#BaseX Errors}} invalid database name.
+
|{{Error|backup|#Errors}} No backup file found.<br/>{{Error|name|#Errors}} invalid database name.<br/>{{Error|conflict|#Errors}} the same database was addressed more than once.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 509: Line 581:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0011|XQuery Errors#BaseX Errors}} invalid database name.<br/>{{Error|BXDB0015|XQuery Errors#BaseX Errors}} No backup found.
+
|{{Error|lock|#Errors}} a database is opened by another process.<br/>{{Error|name|#Errors}} invalid database name.<br/>{{Error|no-backup|#Errors}} No backup found.<br/>{{Error|conflict|#Errors}} the same database was addressed more than once.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 522: Line 594:
 
|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:optimize|$db as xs:string|empty-sequence()}}<br/>{{Func|db:optimize|$db as xs:string, $all as xs:boolean|empty-sequence()}}<br/>{{Func|db:optimize|$db as xs:string, $all as xs:boolean, $options as map(*)|empty-sequence()}}
+
|{{Func|db:optimize|$db as xs:string|empty-sequence()}}<br/>{{Func|db:optimize|$db as xs:string, $all as xs:boolean|empty-sequence()}}<br/>{{Func|db:optimize|$db as xs:string, $all as xs:boolean, $options as map(*)?|empty-sequence()}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
Line 528: Line 600:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|FOUP0002|XQuery Errors#Update Errors}} an error occurred while optimizing the database.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 547: Line 619:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0008|#Errors}} the specified source or target path, or one of its descendants, is invalid.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|path|#Errors}} the specified source or target path, or one of its descendants, is invalid.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 560: Line 632:
 
|-
 
|-
 
| width='120' | '''Signatures'''
 
| width='120' | '''Signatures'''
|{{Func|db:replace|$db as xs:string, $path as xs:string, $input as item()|empty-sequence()}}<br/>{{Func|db:replace|$db as xs:string, $path as xs:string, $input as item(), $options as map(*)|empty-sequence()|empty-sequence()}}
+
|{{Func|db:replace|$db as xs:string, $path as xs:string, $input as item()|empty-sequence()}}<br/>{{Func|db:replace|$db as xs:string, $path as xs:string, $input as item(), $options as map(*)?|empty-sequence()|empty-sequence()}}
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
 
|Replaces a resource, specified by {{Code|$path}}, in the database {{Code|$db}} with the contents of {{Code|$input}}, or adds it as a new resource:
 
|Replaces a resource, specified by {{Code|$path}}, in the database {{Code|$db}} with the contents of {{Code|$input}}, or adds it as a new resource:
* See [[#db:add|db:add]] for more details on the arguments (for historical reasons, the order of the 2nd and 3rd argument differs!).
+
* See [[#db:create|db:create]] for more details on the input argument.
 +
* The parsing behavior can be controlled via {{Code|$options}}:
 +
** allowed options are {{Option|ADDCACHE}} and the [[Options#Parsing|parsing]] and [[Options#XML Parsing|XML parsing]] options, all in lower case
 +
** parsing options will only impact string input (URIs, XML strings), because nodes have already been parsed
 +
* For historical reasons, the order of the 2nd and 3rd argument is different to [[#db:add|db:add]] and [[#db:create|db:create]]
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0014|#Errors}} the path points to a directory.<br/>{{Error|FODC0002|XQuery Errors#Functions Errors}} the input points to an unknown resource.<br/>{{Error|FOUP0001|XQuery Errors#Update Errors}} an attribute was specified as input.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|target|#Errors}} the path points to a directory.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 595: Line 671:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|BXDB0003|#Errors}} the database is not ''persistent'' (stored on disk).<br/>{{Error|FODC0007|XQuery Errors#Functions Errors}} the specified path is invalid.<br/>{{Error|FOUP0002|XQuery Errors#Update Errors}} the resource cannot be stored at the specified location.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|mainmem|#Errors}} the database is not ''persistent'' (stored on disk).
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
 
|
 
|
 
* {{Code|db:store("DB", "video/sample.mov", file:read-binary('video.mov'))}} stores the addressed video file at the specified location.
 
* {{Code|db:store("DB", "video/sample.mov", file:read-binary('video.mov'))}} stores the addressed video file at the specified location.
|}
+
* With the following query, you can copy full directories:
 
+
<pre class="brush:xquery">
==db:output==
+
let $db := 'db'
 
+
let $src-path := 'src/'
{| width='100%'
+
let $trg-path := 'trg/'
|-
+
for $src in db:list($db, $src-path)
| width='120' | '''Signatures'''
+
where db:is-raw($db, $src)
|{{Func|db:output|$result as item()*|empty-sequence()}}
+
let $trg := $trg-path || substring-after($src, $src-path)
|-
+
return db:store($db, $trg, db:retrieve($db, $src))
| '''Summary'''
+
</pre>
|This function can be used to both perform updates and return results in a single query. The argument of the function will be evaluated, and the resulting items will be cached and returned after the updates on the ''pending update list'' have been processed. As nodes may be updated, they will be copied before being cached.<br/>The function can only be used together with [[XQuery Update#Updating Expressions|updating expressions]]; if the function is called within a transform expression, its results will be discarded.
 
|-
 
| '''Examples'''
 
|
 
* {{Code|db:output("Prices have been deleted."), delete node //price}} deletes all {{Code|price}} elements in a database and returns an info message.
 
|}
 
 
 
==db:output-cache==
 
 
 
{| width='100%'
 
|-
 
| width='120' | '''Signatures'''
 
|{{Func|db:output-cache||item()*}}
 
|-
 
| '''Summary'''
 
|Returns the items that have been cached by [[#db:output|db:output]]. It can be used to check which items will eventually be returned as result of an updating function.<br/>This function is ''non-deterministic'': It will return different results before and after items have been cached. It is e. g. useful when writing [[Unit Module|unit tests]].
 
 
|}
 
|}
  
Line 639: Line 699:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|}
 
|}
  
Line 655: Line 715:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0001|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
+
|{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
 
|}
 
|}
  
Line 669: Line 729:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0001|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
+
|{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database.
 
|}
 
|}
  
Line 699: Line 759:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 714: Line 774:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Summary'''
 
| '''Summary'''
Line 735: Line 795:
 
|-
 
|-
 
| '''Errors'''
 
| '''Errors'''
|{{Error|BXDB0002|XQuery Errors#BaseX Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|FODC0002|XQuery Errors#Functions Errors}} the addressed resource is not found or cannot be retrieved.
+
|{{Error|open|#Errors}} the addressed database does not exist or could not be opened.
 
|-
 
|-
 
| '''Examples'''
 
| '''Examples'''
Line 750: Line 810:
 
|Description
 
|Description
 
|-
 
|-
|{{Code|BXDB0001}}
+
|{{Code|args}}
|The referenced XML node is no [[#Database Nodes|database node]], i.e. it is neither stored in a database nor represented as database fragment.
+
|The number of specified inputs and paths differs.
 +
|-
 +
|{{Code|conflict}}
 +
|Multiple update operations point to the same target.
 
|-
 
|-
|{{Code|BXDB0002}}
+
|{{Code|lock}}
|The addressed database does not exist or could not be opened.
+
|A database cannot be updated because it is opened by another process.
 
|-
 
|-
|{{Code|BXDB0003}}
+
|{{Code|mainmem}}
 
|The addressed database is not ''persistent'' (stored on disk).
 
|The addressed database is not ''persistent'' (stored on disk).
 
|-
 
|-
|{{Code|BXDB0004}}
+
|{{Code|name}}
|The database lacks an index structure required by the called function.
+
|The name of the specified database is invalid.
 
|-
 
|-
|{{Code|BXDB0005}}
+
|{{Code|no-backup}}
|A query is expected to exclusively return [[#Database Nodes|database nodes]] of a single database.
+
|No backup exists for a database.
 
|-
 
|-
|{{Code|BXDB0006}}
+
|{{Code|node}}
|A database path addressed with {{Code|doc()}} contains more than one document.
+
|The referenced XML node is no [[#Database Nodes|database node]], i.e. it is neither stored in a database nor represented as database fragment.
 
|-
 
|-
|{{Code|BXDB0007}}
+
|{{Code|no-index}}
|A database cannot be updated because it is opened by another process.
+
|The database lacks an index structure required by the called function.
 
|-
 
|-
|{{Code|BXDB0008}}
+
|{{Code|open}}
|The specified database path is invalid.
+
|The addressed database does not exist or could not be opened.
 
|-
 
|-
|{{Code|BXDB0009}}
+
|{{Code|option}}
|The addressed database id or pre value is out of range.
+
|The specified option is unknown.
 
|-
 
|-
|{{Code|BXDB0011}}
+
|{{Code|path}}
|The name of the specified database is invalid.
+
|The specified database path is invalid.
 
|-
 
|-
|{{Code|BXDB0012}}
+
|{{Code|property}}
|A database can only be created once.
+
|The specified database property is unknown.
 
|-
 
|-
|{{Code|BXDB0013}}
+
|{{Code|range}}
|The number of specified inputs and paths differs.
+
|The addressed database id or pre value is out of range.
 
|-
 
|-
|{{Code|BXDB0014}}
+
|{{Code|target}}
|Path points to a directory.
+
|Path points to an invalid target.
 
|}
 
|}
  
 
=Changelog=
 
=Changelog=
 +
 +
;Version 9.2
 +
 +
* Added: [[#db:dir|db:dir]]
 +
 +
;Version 9.0
 +
 +
* Added: [[#db:option|db:option]]
 +
* Updated: db:output renamed to {{Function|Update|update:output}}, db:output-cache renamed to {{Function|Update|update:cache}}
 +
* Updated: error codes updated; errors now use the module namespace
 +
 +
;Version 8.6
 +
 +
* Added: [[#db:property|db:property]]
  
 
;Version 8.4
 
;Version 8.4
 +
 
* Updated: [[#db:create|db:create]], [[#db:add|db:add]], [[#db:replace|db:replace]]: support for {{Code|ADDCACHE}} option.
 
* Updated: [[#db:create|db:create]], [[#db:add|db:add]], [[#db:replace|db:replace]]: support for {{Code|ADDCACHE}} option.
 
* Added: [[#db:token|db:token]]
 
* Added: [[#db:token|db:token]]
  
 
;Version 8.3
 
;Version 8.3
 +
 
* Updated: [[#db:list-details|db:list-details]]: attributes with name of database and date of backup added to results.
 
* Updated: [[#db:list-details|db:list-details]]: attributes with name of database and date of backup added to results.
 
* Updated: [[#db:backups|db:backups]] now include attributes with name of database and date of backup.
 
* Updated: [[#db:backups|db:backups]] now include attributes with name of database and date of backup.
Line 802: Line 881:
  
 
;Version 8.2
 
;Version 8.2
 +
 
* Added: [[#db:output-cache|db:output-cache]]
 
* Added: [[#db:output-cache|db:output-cache]]
 
* Removed: db:event
 
* Removed: db:event
  
 
;Version 7.9
 
;Version 7.9
 +
 
* Updated: parsing options added to [[#db:create|db:create]], [[#db:add|db:add]] and [[#db:replace|db:replace]].
 
* Updated: parsing options added to [[#db:create|db:create]], [[#db:add|db:add]] and [[#db:replace|db:replace]].
 
* Updated: allow {{Option|UPDINDEX}} if {{Code|$all}} is {{Code|true}}.
 
* Updated: allow {{Option|UPDINDEX}} if {{Code|$all}} is {{Code|true}}.
  
 
;Version 7.8.2
 
;Version 7.8.2
 +
 
* Added: [[#db:alter|db:alter]], [[#db:copy|db:copy]], [[#db:create-backup|db:create-backup]], [[#db:drop-backup|db:drop-backup]], [[#db:restore|db:restore]]
 
* Added: [[#db:alter|db:alter]], [[#db:copy|db:copy]], [[#db:create-backup|db:create-backup]], [[#db:drop-backup|db:drop-backup]], [[#db:restore|db:restore]]
  
 
;Version 7.8
 
;Version 7.8
 +
 
* Removed: db:fulltext (use [[Full-Text Module#ft:search|ft:search]] instead)
 
* Removed: db:fulltext (use [[Full-Text Module#ft:search|ft:search]] instead)
  

Revision as of 14:27, 10 January 2019

This XQuery Module contains functions for processing databases from within XQuery. Existing databases can be opened and listed, its contents can be directly accessed, documents can be added to and removed, etc.

Conventions

All functions and errors in this module are assigned to the http://basex.org/modules/db namespace, which is statically bound to the db prefix.

Database Nodes

Database nodes are XML nodes which are either stored in a persistent database, or which are a node of a main-memory database representation. XML fragments can be converted to a main-memory database by e. g. applying the update or transform expression on a node:

db:node-id(element hello { 'world' } update {})

General Functions

db:system

Signatures db:system() as element(system)
Summary Returns general information on the database system the current values of all global and local Options. The INFO command returns similar output.

db:option

Signatures db:option($name as xs:string) as xs:string
Summary Returns the current value (string, integer, boolean, map) of a global or local Option with the specified $name. The GET command works similar.
Errors option: the specified option is unknown.
Examples
  • db:option('dbpath') returns the database path string.
  • db:option('serializer') returns a map with the current serialization parameters.
  • declare option db:chop 'true'; db:option('chop') returns true (irrespective of the global value).

db:info

Signatures db:info($db as xs:string) as element(database)
Summary Returns meta information on the database $db. The output is similar to the INFO DB command.
Errors open: the addressed database does not exist or could not be opened.

db:property

Signatures db:property($db as xs:string, $name as xs:string) as xs:anyAtomicType
Summary Returns the value (string, boolean, integer) of a property with the specified $name in the database $db. The available properties are the ones returned by db:info.
Errors property: the specified property is unknown.
Examples
  • db:property('db', 'size') returns the number of bytes occupied by the database db.
  • db:property('xmark', 'textindex') indicates if the xmark database has a text index.
  • db:property('discogs', 'uptodate') indicates if the database statistics and index structures of the discogs database are up-to-date.

db:list

Signatures db:list() as xs:string*
db:list($db as xs:string) as xs:string*
db:list($db as xs:string, $path as xs:string) as xs:string*
Summary The result of this function is dependent on the number of arguments:
  • Without arguments, the names of all databases are returned that are accessible to the current user.
  • If a database $db is specified, all documents and raw files of the specified database are returned.
  • The list of returned resources can be restricted by the $path argument.
Errors open: the addressed database does not exist or could not be opened.
Examples
  • db:list("docs") returns the names of all documents of a database named docs.

db:list-details

Signatures db:list-details() as element(database)*
db:list-details($db as xs:string) as element(resource)*
db:list-details($db as xs:string, $path as xs:string) as element(resource)*
Summary Without arguments, an element is returned for each database that is accessible to the current user:
  • An element has a value, which is the name of the database, and several attributes, which contain the number of stored resources, the modification date, the database size on disk (measured in bytes), and a path to the original database input.

If a database $db is specified, an element for each documents and raw file of the specified database is returned:

  • An element has a value, which is the name of the resource, and several attributes, which contain the content type, the modification date, the raw flag (which indicates if the resource is binary or XML), and the size of a resource.
  • The value of the size attribute depends on the resource type: for documents, it represents the number of nodes; for binary data, it represents the file size (measured in bytes).
  • Returned databases resources can be further restricted by the $path argument.
Errors open: the addressed database does not exist or could not be opened.
Examples
  • db:list-details("shop") returns the names plus additional info on all resources of a database named shop.

db:dir

Template:Mark

Signatures db:dir($db as xs:string, $path as xs:string) as element()*
Summary Returns meta data on all directories and resources of the database $db in the specified directory $path. Two types of elements are returned:
  • resource represents a resource. The element value is the directory path; content type, modification date, raw flag (which indicates if the resource is binary or XML), and size of the resource are returned as attributes.
  • dir represents a directory. The element value is the directory path; the modification date is returned as attribute.

Please note that directories are not stored in BaseX. Instead, they result implicitly from the paths of stored resources.

Errors open: the addressed database does not exist or could not be opened.
path: the specified path is invalid.
Examples
  • db:dir('shop', 'books') returns all entries of the books directory of a shop database.

db:backups

Signatures db:backups() as element(backup)*
db:backups($db as xs:string) as element(backup)*
Summary Returns an element sequence containing all available database backups.
If a database $db is specified, the sequence will be restricted to the backups matching this database.
Examples
  • db:backups("factbook") returns all backups that have been made from the factbook database.

Read Operations

db:open

Signatures db:open($db as xs:string) as document-node()*
db:open($db as xs:string, $path as xs:string) as document-node()*
Summary Opens the database $db and returns all document nodes.
The document nodes to be returned can be filtered with the $path argument.
Errors open: the addressed database does not exist or could not be opened.
Examples
  • db:open("docs") returns all documents from the database named docs.
  • db:open("db", "one") returns all documents from the database named db located in the path one.
  • for $i in 1 to 3 return db:open("db" || $i)//item returns all item elements from the databases db1, db2 and db3.

db:open-pre

Signatures db:open-pre($db as xs:string, $pre as xs:integer) as node()
Summary Opens the database $db and returns the node with the specified $pre value.
The PRE value provides very fast access to an existing database node, but it will change whenever a node with a smaller pre values is added to or deleted from a database.
Errors open: the addressed database does not exist or could not be opened.
range: the specified pre value does not exist in the database.
Examples
  • db:open-pre("docs", 0) returns the first database node from the database named docs.

db:open-id

Signatures db:open-id($db as xs:string, $id as xs:integer) as node()
Summary Opens the database $db and returns the node with the specified $id value.
Each database node has a persistent ID value. Access to the node id can be sped up by turning on the UPDINDEX option.
Errors open: the addressed database does not exist or could not be opened.
range: the specified id value 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 the nodes supplied by $nodes, which must all be database nodes.
The PRE value provides very fast access to an existing database node, but it will change whenever a node with a smaller pre values is added to or deleted from a database.
Errors node: $nodes contains a node which is not stored in a database.
Examples
  • db:node-pre(doc("input")) returns 0 if the database input contains a single document.

db:node-id

Signatures db:node-id($nodes as node()*) as xs:integer*
Summary Returns the id values of the nodes supplied by $nodes, which must all be database nodes.
Each database node has a persistent ID value. Access to the node id can be sped up by turning on the UPDINDEX option.
Errors node: $nodes contains a node which is not stored in a database.

db:retrieve

Signatures db:retrieve($db as xs:string, $path as xs:string) as xs:base64Binary
Summary Returns a binary resource addressed by the database $db and $path as streamable xs:base64Binary.
Errors open: the addressed database does not exist or could not be opened.
mainmem: the database is not persistent (stored on disk).
Examples
  • db:retrieve("DB", "music/01.mp3") returns the specified audio file as raw data.
  • stream:materialize(db:retrieve("DB", "music/01.mp3")) materializes the streamable result in main-memory before returning it.
  • convert:binary-to-string(db:retrieve("DB", "info.txt"), 'UTF-8') converts a binary database resource as UTF-8 text and returns a string.

db:export

Signatures db:export($db as xs:string, $path as xs:string) as empty-sequence()
db:export($db as xs:string, $path as xs:string, $params as item()) as empty-sequence()
Summary Exports the specified database $db to the specified file $path. Existing files will be overwritten. The $params argument contains serialization parameters (see Serialization for more details), which can either be specified
  • as children of an <output:serialization-parameters/> element, as defined for the fn:serialize() function; e.g.:
<output:serialization-parameters>
  <output:method value='xml'/>
  <output:cdata-section-elements value="div"/>
  ...
</output:serialization-parameters>
  • as map, which contains all key/value pairs:
map { "method": "xml", "cdata-section-elements": "div", ... }
Errors open: the addressed database does not exist or could not be opened.
Examples Export all files as text:
db:export("DB", "/home/john/xml/texts", map { 'method': 'text' })

The following query can be used to export parts of the database:

let $target := '/home/john/xml/target'
for $doc in db:open('DB', 'collection')
let $path := $target || db:path($doc)
return (
  file:create-dir(file:parent($path)),
  file:write($path, $doc)
)

Value Indexes

db:text

Template:Mark: Support for multiple string values.

Signatures db:text($db as xs:string, $strings as xs:string*) as text()*
Summary Returns all text nodes of the database $db that have one of the specified $strings as values and that are stored in the text index.
Errors open: the addressed database does not exist or could not be opened.
no-index: the index is not available.
Examples
  • db:text("DB", "QUERY")/.. returns the parents of all text nodes of the database DB that match the string QUERY.

db:text-range

Signatures db:text-range($db as xs:string, $min as xs:string, $max as xs:string) as text()*
Summary Returns all text nodes of the database $db that are located in between the $min and $max strings and that are stored in the text index.
Errors open: the addressed database does not exist or could not be opened.
no-index: the index is not available.
Examples
  • db:text-range("DB", "2000", "2001") returns all text nodes of the database DB that are found in between 2000 and 2001.

db:attribute

Template:Mark: Support for multiple string values.

Signatures db:attribute($db as xs:string, $strings as xs:string*) as attribute()*
db:attribute($db as xs:string, $strings as xs:strings*, $name as xs:string) as attribute()*
Summary Returns all attribute nodes of the database $db that have one of the specified $strings as values and that are stored in the attribute index.
If $name is specified, the resulting attribute nodes are filtered by their attribute name.
Errors open: the addressed database does not exist or could not be opened.
no-index: the index is not available.
Examples
  • db:attribute("DB", "QUERY", "id")/.. returns the parents of all id attribute nodes of the database DB that have QUERY as string value.

db:attribute-range

Signatures db:attribute-range($db as xs:string, $min as xs:string, $max as xs:string) as attribute()*
db:attribute-range($db as xs:string, $min as xs:string, $max as xs:string, $name as xs:string) as attribute()*
Summary Returns all attributes of the database $db, the string values of which are larger than or equal to $min and smaller than or equal to $max and that are stored in the attribute index.
Errors open: the addressed database does not exist or could not be opened.
no-index: the index is not available.
Examples
  • db:attribute-range("DB", "id456", "id473", 'id') returns all @id attributes of the database DB that have a string value in between id456 and id473.

db:token

Template:Mark: Support for multiple string values.

Signatures db:token($db as xs:string, $tokens as xs:string*) as attribute()*
db:token($db as xs:string, $tokens as xs:string*, $name as xs:string) as attribute()*
Summary Returns all attribute nodes of the database $db the values of which contain one of the specified $tokens.
If $name is specified, the resulting attribute nodes are filtered by their attribute name.
Errors open: the addressed database does not exist or could not be opened.
no-index: the index is not available.
Examples
  • db:token("DB", "row", "class")/parent::div returns all div nodes of database DB with a class attribute that contains the token row.

Updates

Important note: All functions in this section are updating functions: they will not be immediately executed, but queued on the Pending Update List, which will be processed after the actual query has been evaluated. This means that the order in which the functions are specified in the query does usually not reflect the order in which the code will be evaluated.

db:create

Signatures db:create($db as xs:string) as empty-sequence()
db:create($db as xs:string, $inputs as item()*) as empty-sequence()
db:create($db as xs:string, $inputs as item()*, $paths as xs:string*) as empty-sequence()
db:create($db as xs:string, $inputs as item()*, $paths as xs:string*, $options as map(*)?) as empty-sequence()
Summary Creates a new database with name $db and adds initial documents specified via $inputs to the specified $paths:
  • $inputs may be strings or nodes:
    • nodes may be of any type except for attributes
    • strings can be a URI pointing to a file/directory or an XML string (which is detected by the leading < character)
    • a path must be specified if the input is not a file or directory reference
  • The parsing and indexing behavior can be controlled via $options:
  • An existing database will be overwritten.
  • Database creation takes place after most other update operations (see Pending Update List). As a consequence, a newly created database cannot be addressed in the same query.
Errors lock: a database is opened by another process.
name: the specified name is not a valid database name.
conflict: the same database was addressed more than once.
args: the number of specified inputs and paths differs.
Examples
  • db:create("DB") creates the empty database DB.
  • db:create("DB", "/home/dir/doc.xml") creates the database DB and adds the document /home/dir/doc.xml as initial content.
  • db:create("DB", <a/>, "doc.xml") creates the database DB and adds the document with content <a/> under the name doc.xml.
  • db:create("DB", "/home/dir/", "docs/dir") creates the database DB and adds the documents in /home/dir to the database under the path docs/dir.
  • db:create("DB", file:list('.'), (), map { 'ftindex': true() }) adds all files of the current working directory to a new database, preserving relative filesystem paths and creating a full-text index.

db:drop

Signatures db:drop($db as xs:string) as empty-sequence()
Summary Drops the database $db and all connected resources.
Errors open: the addressed database does not exist or could not be opened.
lock: a database is opened by another process.
conflict: the same database was addressed more than once.
Examples
  • db:drop("DB") drops the database DB.

db:add

Signatures db:add($db as xs:string, $input as item()) as empty-sequence()
db:add($db as xs:string, $input as item(), $path as xs:string) as empty-sequence()
db:add($db as xs:string, $input as item(), $path as xs:string, $options as map(*)?) as empty-sequence()
Summary Adds documents specified by $input to the database $db with the specified $path:
  • A document with the same path may occur more than once in a database. If you want to enforce single instances, use db:replace instead.
  • See db:create for more details on the input argument.
  • The parsing behavior can be controlled via $options:
    • allowed options are ADDCACHE and the parsing and XML parsing options, all in lower case
    • parsing options will only impact string input (URIs, XML strings), because nodes have already been parsed
Errors open: the addressed database does not exist or could not be opened.
Examples
  • db:add("DB", "/home/dir/doc.xml") adds the file /home/dir/doc.xml to the database DB.
  • db:add("DB", <a/>, "doc.xml") adds a document node to the database DB under the name doc.xml.
  • db:add("DB", "/home/dir", "docs/dir", map { 'addcache': true() }) adds all documents in /home/dir to the database DB under the path docs/dir. In order to reduce memory consumption, the files will be cached before being added to the database.

db:delete

Signatures db:delete($db as xs:string, $path as xs:string) as empty-sequence()
Summary Deletes resource(s), specified by $path, from the database $db.
Errors open: the addressed database does not exist or could not be opened.
path: the specified path is invalid.
Examples
  • db:delete("DB", "docs/dir/doc.xml") deletes the resource docs/dir/doc.xml from DB.
  • db:delete("DB", "docs/dir") deletes all resources from DB in the specified path docs/dir.

db:copy

Signatures db:copy($db as xs:string, $name as xs:string) as empty-sequence()
Summary Creates a copy of the database $db, which will be called $name.
Errors open: the addressed database does not exist or could not be opened.
lock: a database is opened by another process.
name: invalid database name.
conflict: the same database was addressed more than once.

db:alter

Signatures db:alter($db as xs:string, $name as xs:string) as empty-sequence()
Summary Renames the database $db to $name.
Errors open: the addressed database does not exist or could not be opened.
lock: a database is opened by another process.
name: invalid database name.
conflict: the same database was addressed more than once.

db:create-backup

Signatures db:create-backup($db as xs:string) as empty-sequence()
Summary Creates a backup of the database $db.
Errors open: the addressed database does not exist or could not be opened.
name: invalid database name.
conflict: the same database was addressed more than once.
Examples
  • db:create-backup("DB") creates a backup of the database DB.

db:drop-backup

Signatures db:drop-backup($name as xs:string) as empty-sequence()
Summary Drops all backups of the database with the specified $name. If the given $name points to a specific backup file, only this specific backup file is deleted.
Errors backup: No backup file found.
name: invalid database name.
conflict: the same database was addressed more than once.
Examples
  • db:drop-backup("DB") drops all backups of the database DB.
  • db:drop-backup("DB-2014-03-13-17-36-44") drops the specific backup file DB-2014-03-13-17-36-44.zip of the database DB.

db:restore

Signatures db:restore($name as xs:string) as empty-sequence()
Summary Restores the database with the specified $name. The $name may include the timestamp of the backup file.
Errors lock: a database is opened by another process.
name: invalid database name.
no-backup: No backup found.
conflict: the same database was addressed more than once.
Examples
  • db:restore("DB") restores the database DB.
  • db:restore("DB-2014-03-13-18-05-45") restores the database DB from the backup file with the given timestamp.

db:optimize

Signatures db:optimize($db as xs:string) as empty-sequence()
db:optimize($db as xs:string, $all as xs:boolean) as empty-sequence()
db:optimize($db as xs:string, $all as xs:boolean, $options as map(*)?) as empty-sequence()
Summary Optimizes the meta data and indexes of the database $db.
If $all is true, the complete database will be rebuilt.
The $options argument can be used to control indexing. The syntax is identical to the db:create function: Allowed options are all indexing and full-text options. UPDINDEX is only supported if $all is true.
Errors open: the addressed database does not exist or could not be opened.
Examples
  • db:optimize("DB") optimizes the database structures of the database DB.
  • db:optimize("DB", true(), map { 'ftindex': true() }) optimizes all database structures of the database DB and creates a full-text index.

db:rename

Signatures db:rename($db as xs:string, $source as xs:string, $target as xs:string) as empty-sequence()
Summary Moves all resources(s) of database $db, which are found in the supplied $source path, to the supplied $target path. The paths may point to single resources or directories. No updates will take place if a non-existing source path is supplied.
Errors open: the addressed database does not exist or could not be opened.
path: the specified source or target path, or one of its descendants, is invalid.
Examples
  • db:rename("DB", "docs/dir/doc.xml", "docs/dir/newdoc.xml") renames the resource docs/dir/doc.xml to docs/dir/newdoc.xml in the database DB.
  • db:rename("DB", "docs/dir", "docs/newdir") moves all resources in the database DB from docs/dir to {Code|docs/newdir}}.

db:replace

Signatures db:replace($db as xs:string, $path as xs:string, $input as item()) as empty-sequence()
db:replace($db as xs:string, $path as xs:string, $input as item(), $options as map(*)?) as empty-sequence()
Summary Replaces a resource, specified by $path, in the database $db with the contents of $input, or adds it as a new resource:
  • See db:create for more details on the input argument.
  • The parsing behavior can be controlled via $options:
    • allowed options are ADDCACHE and the parsing and XML parsing options, all in lower case
    • parsing options will only impact string input (URIs, XML strings), because nodes have already been parsed
  • For historical reasons, the order of the 2nd and 3rd argument is different to db:add and db:create
Errors open: the addressed database does not exist or could not be opened.
target: the path points to a directory.
Examples
  • db:replace("DB", "docs/dir/doc.xml", "/home/dir/doc.xml") replaces the content of the document docs/dir/doc.xml in the database DB with the content of the file /home/dir/doc.xml.
  • db:replace("DB", "docs/dir/doc.xml", "<a/>") replaces the content of the document docs/dir/doc.xml in the database DB with <a/>.
  • db:replace("DB", "docs/dir/doc.xml", document { <a/> }) replaces the content of the document docs/dir/doc.xml in the database DB with the specified document node.

The following query can be used to import files from a directory to a database:

let $source := '/home/john/xml/source'
for $file in file:list($source, true())
let $path := $source || $file
where not(file:is-dir($path))
return db:replace('db', $file, doc($path))

db:store

Signatures db:store($db as xs:string, $path as xs:string, $input as item()) as empty-sequence()
Summary Replaces a binary resource specified by $input in the database $db and the location specified by $path, or adds it as new resource.
Errors open: the addressed database does not exist or could not be opened.
mainmem: the database is not persistent (stored on disk).
Examples
  • db:store("DB", "video/sample.mov", file:read-binary('video.mov')) stores the addressed video file at the specified location.
  • With the following query, you can copy full directories:
let $db := 'db'
let $src-path := 'src/'
let $trg-path := 'trg/'
for $src in db:list($db, $src-path)
where db:is-raw($db, $src)
let $trg := $trg-path || substring-after($src, $src-path)
return db:store($db, $trg, db:retrieve($db, $src))

db:flush

Signatures db:flush($db as xs:string) as empty-sequence()
Summary Explicitly flushes the buffers of the database $db. This command is only useful if AUTOFLUSH has been set to false.
Errors open: the addressed database does not exist or could not be opened.

Helper Functions

db:name

Signatures db:name($node as node()) as xs:string
Summary Returns the name of the database in which the specified database node $node is stored.
Errors node: $nodes contains a node which is not stored in a database.

db:path

Signatures db:path($node as node()) as xs:string
Summary Returns the path of the database document in which the specified database node $node is stored.
Errors node: $nodes contains a node which is not stored in a database.

db:exists

Signatures db:exists($db as xs:string) as xs:boolean
db:exists($db as xs:string, $path as xs:string) as xs:boolean
Summary Checks if the database $db or the resource specified by $path exists. false is returned if a database directory has been addressed.
Examples
  • db:exists("DB") returns true if the database DB exists.
  • db:exists("DB", "resource") returns true if resource is an XML document or a raw file.

db:is-raw

Signatures db:is-raw($db as xs:string, $path as xs:string) as xs:boolean
Summary Checks if the specified resource in the database $db and the path $path exists, and if it is a binary resource.
Errors open: the addressed database does not exist or could not be opened.
Examples
  • db:is-raw("DB", "music/01.mp3") returns true.

db:is-xml

Signatures db:is-xml($db as xs:string, $path as xs:string) as xs:boolean
Errors open: the addressed database does not exist or could not be opened.
Summary Checks if the specified resource in the database $db and the path $path exists, and if it is an XML document.
Examples
  • db:is-xml("DB", "dir/doc.xml") returns true.

db:content-type

Signatures db:content-type($db as xs:string, $path as xs:string) as xs:string
Summary Retrieves the content type of a resource in the database $db and the path $path.
The file extension is used to recognize the content-type of a resource stored in the database. Content-type application/xml will be returned for any XML document stored in the database, regardless of its file name extension.
Errors open: the addressed database does not exist or could not be opened.
Examples
  • db:content-type("DB", "docs/doc01.pdf") returns application/pdf.
  • db:content-type("DB", "docs/doc01.xml") returns application/xml.
  • db:content-type("DB", "docs/doc01") returns application/xml, if db:is-xml("DB", "docs/doc01") returns true.

Errors

Code Description
args The number of specified inputs and paths differs.
conflict Multiple update operations point to the same target.
lock A database cannot be updated because it is opened by another process.
mainmem The addressed database is not persistent (stored on disk).
name The name of the specified database is invalid.
no-backup No backup exists for a database.
node The referenced XML node is no database node, i.e. it is neither stored in a database nor represented as database fragment.
no-index The database lacks an index structure required by the called function.
open The addressed database does not exist or could not be opened.
option The specified option is unknown.
path The specified database path is invalid.
property The specified database property is unknown.
range The addressed database id or pre value is out of range.
target Path points to an invalid target.

Changelog

Version 9.2
Version 9.0
Version 8.6
Version 8.4
Version 8.3
  • Updated: db:list-details: attributes with name of database and date of backup added to results.
  • Updated: db:backups now include attributes with name of database and date of backup.
  • Updated: Value Indexes: raise error if no index exists.
Version 8.2
Version 7.9
Version 7.8.2
Version 7.8
Version 7.7
Version 7.6
  • Updated: db:create: allow more than one input and path.
Version 7.5
Version 7.3
Version 7.2.1
Version 7.1
Version 7.0