Difference between revisions of "Database Module"
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− | This | + | This [[Module Library|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 <code><nowiki>http://basex.org/modules/db</nowiki></code> namespace, which is statically bound to the {{Code|db}} prefix.<br/> | ||
+ | |||
+ | ==Database Nodes== | ||
+ | |||
+ | In BaseX, two internal representations exist for XML nodes: | ||
+ | |||
+ | 1. Database nodes are: | ||
+ | * stored in a persistent database on disk; | ||
+ | * nodes of a document that has been generated temporarily with {{Code|fn:doc}}, {{Code|fn:parse-xml}} and other functions; or | ||
+ | * the result of a [[XQuery Update#Main-Memory Updates|main-memory update]]. | ||
+ | 2. Fragments are similar to DOM structures. They are created when XQuery node constructors are used (<code><a/></code>, <code>element a { }</code>, etc.). | ||
+ | |||
+ | Fragments require less memory for small XML structures, but database nodes are more efficient for larger amounts of data. Fragments nodes can be converted to database nodes by applying a [[XQuery_Update#Main-Memory Updates|main-memory update]] with an empty body to a node: | ||
+ | |||
+ | <pre lang='xquery'> | ||
+ | <xml>hello world</xml> update { } | ||
+ | </pre> | ||
+ | |||
+ | ==Updating Functions== | ||
+ | |||
+ | Various functions in this module are ''updating''. Updating functions will not be immediately executed, but queued on the [[XQuery Update#Pending Update List|Pending Update List]], and processed after the remaining query has been evaluated. This means that the order in which the functions are specified in the query often does not reflect the order in which they will eventually be executed. | ||
+ | |||
+ | =General Functions= | ||
==db:system== | ==db:system== | ||
− | {| | + | |
− | |- | + | {| width='100%' |
− | | valign='top' | + | |- valign="top" |
− | |<code>< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:system() as element(system)</pre> |
− | | valign='top' | '''Summary''' | + | |- valign="top" |
− | | | + | | '''Summary''' |
+ | |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%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:option( | ||
+ | $name as xs:string | ||
+ | ) as xs:string</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns the current value (string, integer, boolean, map) of a global or local [[Options|Option]] with the specified {{Code|$name}}. The {{Command|SHOW OPTIONS}} command returns similar output. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|option|#Errors}} the specified option is unknown. | ||
+ | |- valign="top" | ||
+ | | '''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:stripws 'true'; db:option('stripws')</code> returns the locally assigned value. | ||
+ | |} | ||
+ | |||
+ | ==db:info== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:info( | ||
+ | $database as xs:string | ||
+ | ) as element(database)</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns meta information on the specified {{Code|$database}}. The output is similar to the {{Command|INFO DB}} command. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |} | ||
+ | |||
+ | ==db:property== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:property( | ||
+ | $database as xs:string, | ||
+ | $name as xs:string | ||
+ | ) as xs:anyAtomicType</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns the value (string, boolean, integer) of a property with the specified {{Code|$name}} in the specified {{Code|$database}}. The available properties are the ones returned by {{Function||db:info}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|property|#Errors}} the specified property is unknown. | ||
+ | |- valign="top" | ||
+ | | '''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. | ||
|} | |} | ||
==db:list== | ==db:list== | ||
− | {| | + | |
− | |- | + | {| width='100%' |
− | + | |- valign="top" | |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:list( |
− | + | $database as xs:string := (), | |
− | | | + | $path as xs:string := () |
+ | ) as xs:string*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Without arguments, the names of all databases are returned that are accessible to the current user. If {{Code|$database}} is specified, paths to all resources of this database are returned. The results can be restricted to resources starting with the specified {{Code|$path}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:list("docs")}} returns the names of all documents of a database named {{Code|docs}}. | ||
|} | |} | ||
− | ==db: | + | ==db:list-details== |
− | {| | + | |
− | |- | + | {| width='100%' |
− | + | |- valign="top" | |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:list-details( |
− | + | $database as xs:string := (), | |
− | | | + | $path as xs:string := () |
− | |- | + | ) as element()*</pre> |
− | + | |- valign="top" | |
− | | | + | | '''Summary''' |
− | |- | + | |Without arguments, an element is returned for each database that is accessible to the current user: |
− | + | * An element has a value, which is the name of the database, and several attributes, which contain the number of stored resources, the modification date, the database size on disk (measured in bytes), and a path to the original database input. | |
+ | If {{Code|$database}} is specified, an element for each resource in this 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). | ||
+ | * The results can be restricted to resources starting with the specified {{Code|$path}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
| | | | ||
− | * | + | * {{Code|db:list-details("shop")}} returns the names plus additional info on all resources of a database named {{Code|shop}}. |
− | |||
|} | |} | ||
− | ==db: | + | ==db:dir== |
− | {| | + | |
− | |- | + | {| width='100%' |
− | + | |- valign="top" | |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:dir( |
− | + | $database as xs:string, | |
− | | | + | $path as xs:string |
− | |- | + | ) as element()*</pre> |
− | + | |- valign="top" | |
− | | | + | | '''Summary''' |
− | |- | + | |Returns metadata on all directories and resources of a {{Code|$database}} in the specified {{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 in an attribute. | ||
+ | The directories are not stored in the internal database layout. Instead, they result implicitly from the paths of stored resources. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|path|#Errors}} the specified path is invalid. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
| | | | ||
− | * | + | * {{Code|db:dir('shop', 'books')}} returns all entries of the {{Code|books}} directory of a {{Code|shop}} database. |
|} | |} | ||
− | ==db: | + | =Read Operations= |
− | {| | + | |
− | |- | + | ==db:get== |
− | | valign='top' | + | |
− | + | {| width='100%' | |
− | |- | + | |- valign="top" |
− | + | | width='120' | '''Signature''' | |
− | | | + | |<pre>db:get( |
− | |- | + | $database as xs:string, |
− | + | $path as xs:string := () | |
− | |< | + | ) as document-node()*</pre> |
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns all documents from the specified {{Code|$database}}, or only documents matching the specified {{Code|$path}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:get('docs')}} returns all documents from the database named {{Code|docs}}. | ||
+ | * {{Code|db:get('db', 'one')}} returns all documents from the database named {{Code|db}} located in the path {{Code|one}}. | ||
+ | * <code>for $i in 1 to 3 return db:get('db' || $i)//item</code> returns all item elements from the databases {{Code|db1}}, {{Code|db2}} and {{Code|db3}}. | ||
+ | |} | ||
+ | |||
+ | ==db:get-pre== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:get-pre( | ||
+ | $database as xs:string, | ||
+ | $values as xs:integer* | ||
+ | ) as node()*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns all nodes from a {{Code|$database}} with the specified PRE {{Code|values}} in [[Utility Module#util:ddo|distinct document order]].<br/>The [[Node Storage#PRE Value|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. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:get-pre("docs", 0)}} returns the first database node from the database named {{Code|docs}}. | ||
+ | |} | ||
+ | |||
+ | ==db:get-id== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:get-id( | ||
+ | $database as xs:string, | ||
+ | $values as xs:integer* | ||
+ | ) as node()*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns all nodes from a {{Code|$database}} with the specified ID {{Code|$values}} in [[Utility Module#util:ddo|distinct document order]].<br/>Each database node has a ''persistent'' [[Node Storage#ID Value|ID value]]. Access to the node ID can be sped up by turning on the {{Option|UPDINDEX}} option. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |} | ||
+ | |||
+ | ==db:get-binary== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:get-binary( | ||
+ | $database as xs:string, | ||
+ | $path as xs:string | ||
+ | ) as item()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns a map with the paths and binary items of all resources in the specified {{Code|$database}}. A single {{Code|xs:base64Binary}} item is returned if a {{Code|$path}} is specified. All items are [[Lazy Module|lazy]], i.e., the actual data will only be retrieved if it is processed. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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). | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:get-binary('DB', 'music/01.mp3')}} returns the specified audio file as raw data. | ||
+ | * <code><nowiki>stream:materialize(db:get-binary('DB', 'music/01.mp3'))</nowiki></code> materializes the streamable result in main-memory before returning it. | ||
+ | * <code><nowiki>convert:binary-to-string(db:get-binary('DB', 'info.txt'), 'UTF-8')</nowiki></code> converts a binary database resource as UTF-8 text and returns a string. | ||
+ | |} | ||
+ | |||
+ | ==db:get-value== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:get-value( | ||
+ | $database as xs:string, | ||
+ | $path as xs:string | ||
+ | ) as item()*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns a map with the paths and values of all resources in the specified {{Code|$database}}. A single value is returned if a {{Code|$path}} is specified. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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). | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:get-value('DB', 'sequence')}} returns the specified sequence. | ||
|} | |} | ||
==db:node-pre== | ==db:node-pre== | ||
− | {| | + | |
− | |- | + | {| width='100%' |
− | + | |- valign="top" | |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:node-pre( |
− | + | $nodes as node()* | |
− | |Returns the | + | ) as xs:integer*</pre> |
− | |- | + | |- valign="top" |
− | + | | '''Summary''' | |
+ | |Returns the PRE values of the specified {{Code|$nodes}}, which must all be [[#Database Nodes|database nodes]].<br/>The [[Node Storage#PRE Value|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. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
| | | | ||
− | * | + | * {{Code|db:node-pre(doc("input"))}} returns {{Code|0}} if the database {{Code|input}} contains a single document. |
|} | |} | ||
==db:node-id== | ==db:node-id== | ||
− | {| | + | |
− | |- | + | {| width='100%' |
− | + | |- valign="top" | |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:node-id( |
− | + | $nodes as node()* | |
− | |Returns the | + | ) as xs:integer*</pre> |
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns the ID values of the specified {{Code|$nodes}}, which must all be [[#Database Nodes|database nodes]].<br/>Each database node has a ''persistent'' [[Node Storage#ID Value|ID value]]. Access to the node id can be sped up by turning on the {{Option|UPDINDEX}} option. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database. | ||
|} | |} | ||
+ | |||
+ | ==db:export== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:export( | ||
+ | $database as xs:string, | ||
+ | $path as xs:string, | ||
+ | $options as map(*)? := map { } | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Exports the specified {{Code|$database}} to the specified file {{Code|$path}}. Existing files will be overwritten.<br/>The {{Code|$options}} argument contains [[Serialization|serialization parameters]] (see [https://www.w3.org/TR/xpath-functions-31/#func-serialize fn:serialize]). | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | Export all files as text:<br/> | ||
+ | <pre lang='xquery'> | ||
+ | db:export("DB", "/home/john/xml/texts", map { 'method': 'text' }) | ||
+ | </pre> | ||
+ | The following code can be used to export parts of the database: | ||
+ | <pre lang='xquery'> | ||
+ | let $target := '/home/john/xml/target' | ||
+ | for $doc in db:get('DB', 'collection') | ||
+ | let $path := $target || db:path($doc) | ||
+ | return ( | ||
+ | file:create-dir(file:parent($path)), | ||
+ | file:write($path, $doc) | ||
+ | ) | ||
+ | </pre> | ||
+ | |} | ||
+ | |||
+ | =Value Indexes= | ||
==db:text== | ==db:text== | ||
− | {| | + | |
− | |- | + | {| width='100%' |
− | + | |- valign="top" | |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:text( |
− | + | $database as xs:string, | |
− | |Returns all text nodes that | + | $values as xs:string* |
− | |- | + | ) as text()*</pre> |
− | + | |- valign="top" | |
+ | | '''Summary''' | ||
+ | |Returns all text nodes of a {{Code|$database}} that match one of the specified {{Code|$values}} and that are stored in the text index. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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/> | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
| | | | ||
− | * | + | * {{Code|db:text("DB", "QUERY")/..}} returns the parents of all text nodes of the database {{Code|DB}} that match the string {{Code|QUERY}}. |
+ | |} | ||
+ | |||
+ | ==db:text-range== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:text-range( | ||
+ | $database as xs:string, | ||
+ | $min as xs:string, | ||
+ | $max as xs:string | ||
+ | ) as text()*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns all text nodes of a {{Code|$database}} whose values are larger than or equal to {{Code|$min}} and smaller than or equal to {{Code|$max}} and that are stored in the text index. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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/> | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:text-range("DB", "2000", "2001")}} returns all text nodes of the database {{Code|DB}} that are found in between {{Code|2000}} and {{Code|2001}}. | ||
|} | |} | ||
==db:attribute== | ==db:attribute== | ||
− | {| | + | |
− | |- | + | {| width='100%' |
− | | valign='top' width=' | + | |- valign="top" |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:attribute( |
− | | valign= | + | $database as xs:string, |
− | | | + | $values as xs:string*, |
− | |- | + | $name as xs:string := () |
− | | valign='top' | '''Examples''' | + | ) as attribute()*</pre> |
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns all attribute nodes of a {{Code|$database}} that match one of the specified {{Code|$values}} and that are stored in the attribute index.<br/>If {{Code|$name}} is specified, the resulting attribute nodes are filtered by their attribute name. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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/> | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:attribute("DB", "QUERY", "id")/..}} returns the parents of all {{Code|id}} attribute nodes of the database {{Code|DB}} that have {{Code|QUERY}} as string value. | ||
+ | |} | ||
+ | |||
+ | ==db:attribute-range== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:attribute-range( | ||
+ | $database as xs:string, | ||
+ | $min as xs:string, | ||
+ | $max as xs:string, | ||
+ | $name as xs:string := () | ||
+ | ) as attribute()*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns all attributes of a {{Code|$database}} whose values are larger than or equal to {{Code|$min}} and smaller than or equal to {{Code|$max}} and that are stored in the attribute index. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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/> | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:attribute-range("DB", "id456", "id473", 'id')}} returns all {{Code|@id}} attributes of the database {{Code|DB}} that have a string value in between {{Code|id456}} and {{Code|id473}}. | ||
+ | |} | ||
+ | |||
+ | ==db:token== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:token( | ||
+ | $database as xs:string, | ||
+ | $tokens as xs:string*, | ||
+ | $name as xs:string := () | ||
+ | ) as attribute()*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns all attribute nodes of a {{Code|$database}} 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. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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/> | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:token("DB", "row", "class")/parent::div}} returns all {{Code|div}} nodes of database {{Code|DB}} with a {{Code|class}} attribute that contains the token {{Code|row}}. | ||
+ | |} | ||
+ | |||
+ | =Updates= | ||
+ | |||
+ | All functions in this section are [[#Updating Functions|Updating Functions]]. | ||
+ | |||
+ | ==db:create== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:create( | ||
+ | $database as xs:string, | ||
+ | $inputs as item()* := (), | ||
+ | $paths as xs:string* := (), | ||
+ | $options as map(*)? := map { } | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Creates a new {{Code|$database}} and adds the supplied {{Code|$inputs}} to the specified {{Code|$paths}}: | ||
+ | * The 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 <code><</code> 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 {{Code|$options}}: | ||
+ | ** 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 will only impact string input (URIs, XML strings) because nodes have already been parsed. | ||
+ | * 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. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:create("DB")}} creates the empty database {{Code|DB}}. | ||
+ | * {{Code|db:create("DB", "/home/dir/doc.xml")}} creates the database {{Code|DB}} and adds the document {{Code|/home/dir/doc.xml}} as initial content. | ||
+ | * {{Code|db:create("DB", <a/>, "doc.xml")}} creates the database {{Code|DB}} and adds the document with content {{Code|<a/>}} under the name {{Code|doc.xml}}. | ||
+ | * {{Code|db:create("DB", "/home/dir/", "docs/dir")}} creates the database {{Code|DB}} and adds the documents in {{Code|/home/dir}} to the database under the path {{Code|docs/dir}}. | ||
+ | * <code>db:create("DB", file:list('.'), (), map { 'ftindex': true() })</code> adds all files of the current working directory to a new database, preserving relative filesystem paths and creating a full-text index. | ||
+ | |} | ||
+ | |||
+ | ==db:add== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:add( | ||
+ | $database as xs:string, | ||
+ | $input as item(), | ||
+ | $path as xs:string? := (), | ||
+ | $options as map(*)? := map { } | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Adds the specified {{Code|$input}} to a {{Code|$database}} with the specified {{Code|$path}}: | ||
+ | * A document with the same path may occur more than once in a database. If you want to enforce single instances, use {{Function||db:put}} instead. | ||
+ | * See {{Function||db:create}} for more details on the input and path arguments. | ||
+ | * 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 | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * <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")</code> adds a document node to the database {{Code|DB}} under the name {{Code|doc.xml}}. | ||
+ | * <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}}. To reduce memory consumption, the files will be cached before being added to the database. | ||
+ | |} | ||
+ | |||
+ | ==db:put== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:put( | ||
+ | $database as xs:string, | ||
+ | $input as item(), | ||
+ | $path as xs:string, | ||
+ | $options as map(*)? := map { } | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Replaces a resource, specified by {{Code|$path}}, in a {{Code|$database}} with the contents of {{Code|$input}}, or adds it as a new resource: | ||
+ | * 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. | ||
+ | * See {{Function||db:create}} for more details on the input argument. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|target|#Errors}} the path points to a directory. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:put("DB", "/home/dir/doc.xml", "docs/dir/doc.xml")}} replaces the content of the document {{Code|docs/dir/doc.xml}} in the database {{Code|DB}} with the content of the file {{Code|/home/dir/doc.xml}}. | ||
+ | * {{Code|db:put("DB", "<a/>", "docs/dir/doc.xml")}} replaces the content of the document {{Code|docs/dir/doc.xml}} in the database {{Code|DB}} with {{Code|<a/>}}. | ||
+ | * {{Code|db:put("DB", document { <a/> }, "docs/dir/doc.xml")}} replaces the content of the document {{Code|docs/dir/doc.xml}} in the database {{Code|DB}} with the specified document node. | ||
+ | The following query can be used to import files from a directory to a database: | ||
+ | <pre lang='xquery'> | ||
+ | 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:put('db', doc($path), $file) | ||
+ | </pre> | ||
+ | |} | ||
+ | |||
+ | ==db:put-binary== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:put-binary( | ||
+ | $database as xs:string, | ||
+ | $input as item(), | ||
+ | $path as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Stores a binary resource specified by {{Code|$input}} in a {{Code|$database}} at the specified {{Code|$path}}. Existing resources are overwritten. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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). | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:put-binary('DB', file:read-binary('video.mov'), 'video/sample.mov')}} stores the addressed video file at the specified location. | ||
+ | * With the following query, you can copy the binary resources of one database into another: | ||
+ | <pre lang='xquery'> | ||
+ | let $db := 'db' | ||
+ | let $src-path := 'src/' | ||
+ | let $trg-path := 'trg/' | ||
+ | for $src in db:list($db, $src-path) | ||
+ | where db:type($db, $src) = 'binary' | ||
+ | let $trg := $trg-path || substring-after($src, $src-path) | ||
+ | return db:put-binary($db, db:get-binary($db, $src), $trg) | ||
+ | </pre> | ||
+ | |} | ||
+ | |||
+ | ==db:put-value== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:put-value( | ||
+ | $database as xs:string, | ||
+ | $input as item()*, | ||
+ | $path as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Stores an {{Code|$input}} value in a {{Code|$database}} at the specified {{Code|$path}}. Existing resources are overwritten. The value can be an arbitrary sequence of atomic items, nodes, maps, and arrays. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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). | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:put-value('DB', 1 to 10000, 'sequence')}} stores a numeric range in the database. | ||
+ | * With the following query, a map with countries and associated cities is stored in a database. The value resource can e.g. be used as index in future queries: | ||
+ | <pre lang='xquery'> | ||
+ | db:put-value( | ||
+ | 'factbook', | ||
+ | map:merge( | ||
+ | for $country in db:get('factbook')//country | ||
+ | return map:entry($country/@name, $country//city/name ! string()) | ||
+ | ), | ||
+ | 'cities' | ||
+ | )</pre> | ||
+ | |} | ||
+ | |||
+ | ==db:delete== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:delete( | ||
+ | $database as xs:string, | ||
+ | $path as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Deletes resource(s), specified by {{Code|$path}}, from the specified {{Code|$database}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened.<br/>{{Error|path|#Errors}} the specified path is invalid. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:delete("DB", "docs/dir/doc.xml")}} deletes the resource {{Code|docs/dir/doc.xml}} from {{Code|DB}}. | ||
+ | * {{Code|db:delete("DB", "docs/dir")}} deletes all resources from {{Code|DB}} in the specified path {{Code|docs/dir}}. | ||
+ | |} | ||
+ | |||
+ | ==db:copy== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:copy( | ||
+ | $database as xs:string, | ||
+ | $new-name as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Creates a copy of {{Code|$database}}, which will be called {{Code|$new-name}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |} | ||
+ | |||
+ | ==db:alter== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:alter( | ||
+ | $database as xs:string, | ||
+ | $new-name as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Renames a {{Code|$database}} to {{Code|$new-name}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |} | ||
+ | |||
+ | ==db:optimize== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:optimize( | ||
+ | $database as xs:string, | ||
+ | $all as xs:boolean? := false(), | ||
+ | $options as map(*)? := map { } | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Optimizes the metadata and indexes of a {{Code|$database}}.<br/>If {{Code|$all}} is {{Code|true}}, the complete database will be rebuilt.<br/>The {{Code|$options}} argument can be used to control indexing. The syntax is identical to the {{Function||db:create}} function: Allowed options are all [[Options#Indexing|indexing]] and [[Options#Full-Text|full-text]] options. {{Option|UPDINDEX}} is only supported if {{Code|$all}} is {{Code|true}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
| | | | ||
− | * <code>db: | + | * {{Code|db:optimize("DB")}} optimizes the database structures of the database {{Code|DB}}. |
+ | * <code>db:optimize("DB", true(), map { 'ftindex': true() })</code> optimizes all database structures of the database {{Code|DB}} and creates a full-text index. | ||
|} | |} | ||
− | ==db: | + | ==db:rename== |
− | {| | + | |
− | |- | + | {| width='100%' |
− | + | |- valign="top" | |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:rename( |
− | + | $database as xs:string, | |
− | | | + | $source as xs:string, |
− | |- | + | $target as xs:string |
− | + | ) as empty-sequence()</pre> | |
− | | | + | |- valign="top" |
− | |- | + | | '''Summary''' |
− | + | |Moves all resources(s) of a {{Code|$database}}, which are found in the supplied {{Code|$source}} path, to the supplied {{Code|$target}} path. The paths may point to single resources or directories. No updates will take place if a non-existing source path is supplied. | |
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
| | | | ||
− | * | + | * {{Code|db:rename("DB", "docs/dir/doc.xml", "docs/dir/newdoc.xml")}} renames the resource {{Code|docs/dir/doc.xml}} to {{Code|docs/dir/newdoc.xml}} in the database {{Code|DB}}. |
+ | * {{Code|db:rename("DB", "docs/dir", "docs/newdir")}} moves all resources in the database {{Code|DB}} from {{Code|docs/dir}} to {{Code|docs/newdir}}. | ||
|} | |} | ||
− | ==db: | + | ==db:flush== |
− | {| | + | |
− | |- | + | {| width='100%' |
− | | valign='top' width=' | + | |- valign="top" |
− | |< | + | | width='120' | '''Signature''' |
− | |- | + | |<pre>db:flush( |
− | | valign= | + | $database as xs:string |
− | | | + | ) as empty-sequence()</pre> |
− | |- | + | |- valign="top" |
− | | valign='top' | ''' | + | | '''Summary''' |
− | |< | + | |Explicitly flushes the buffers of a {{Code|$database}}. This command is only useful if {{Option|AUTOFLUSH}} has been set to {{Code|false}}. |
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |} | ||
+ | |||
+ | ==db:drop== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:drop( | ||
+ | $database as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Drops a {{Code|$database}} and all connected resources. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:drop("DB")}} drops the database {{Code|DB}}. | ||
+ | |} | ||
+ | |||
+ | =Backups= | ||
+ | |||
+ | All functions in this section except for {{Function||db:backups}} are {{Function|Database|Updating Functions}}. | ||
+ | |||
+ | ==db:create-backup== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:create-backup( | ||
+ | $database as xs:string, | ||
+ | $options as map(*)? := map { } | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Creates a backup of a {{Code|$database}}. If no name is supplied, general data will be backed up. The following {{Code|$options}} are available: | ||
+ | * With {{Code|comment}}, a comment string can be attached to the backup. | ||
+ | * By setting {{Code|compress}} to false, the backup will be created faster, but it will take more space on disk. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:create-backup('DB', map { 'compress': false() })}} creates a backup of the database {{Code|DB}} without compressing its entries. | ||
+ | |} | ||
+ | |||
+ | ==db:drop-backup== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:drop-backup( | ||
+ | $name as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Drops all backups of the database with the specified {{Code|$name}}. If the name ends with a timestamp, only the specified backup file will be deleted. If no name is supplied, backups with general data are addressed. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:drop-backup("DB")}} drops all backups of the database {{Code|DB}}. | ||
+ | * {{Code|db:drop-backup("DB-2014-03-13-17-36-44")}} drops the specific backup file {{Code|DB-2014-03-13-17-36-44.zip}} of the database {{Code|DB}}. | ||
+ | |} | ||
+ | |||
+ | ==db:alter-backup== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:alter-backup( | ||
+ | $name as xs:string, | ||
+ | $new-name as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Renames all backups of the database with the specified {{Code|$name}} to {{Code|$new-name}}. If the name ends with a date, only the specified backup file will be renamed. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:alter-backup("DB", "DB2)}} renames all backups of the database {{Code|DB}} to {{Code|DB2}}. | ||
+ | |} | ||
+ | |||
+ | ==db:restore== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:restore( | ||
+ | $name as xs:string | ||
+ | ) as empty-sequence()</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Restores the database with the specified {{Code|$name}}. The {{Code|$name}} may include the timestamp of the backup file. If no name is supplied, general data will be restored. If general data is restored, it will only be available after BaseX has been restarted. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{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. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:restore("DB")}} restores the database {{Code|DB}}. | ||
+ | * {{Code|db:restore("DB-2014-03-13-18-05-45")}} restores the database {{Code|DB}} from the backup file with the given timestamp. | ||
+ | |} | ||
+ | |||
+ | ==db:backups== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:backups( | ||
+ | $database as xs:string := () | ||
+ | ) as element(backup)*</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns an element sequence containing all available database backups with timestamp, file size and comment.<br/>If a {{Code|$database}} is specified, the sequence will be restricted to the backups matching this database. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:backups("factbook")}} returns all backups that have been made from the {{Code|factbook}} database. | ||
+ | |} | ||
+ | |||
+ | =Helper Functions= | ||
+ | |||
+ | ==db:name== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:name( | ||
+ | $node as node() | ||
+ | ) as xs:string</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns the name of the database in which the specified [[#Database Nodes|database node]] {{Code|$node}} is stored. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database. | ||
+ | |} | ||
+ | |||
+ | ==db:path== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:path( | ||
+ | $node as node() | ||
+ | ) as xs:string</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns the path of the database document in which the specified [[#Database Nodes|database node]] {{Code|$node}} is stored. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|node|#Errors}} {{Code|$nodes}} contains a node which is not stored in a database. | ||
+ | |} | ||
+ | |||
+ | ==db:exists== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:exists( | ||
+ | $database as xs:string, | ||
+ | $path as xs:string := () | ||
+ | ) as xs:boolean</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Checks if a {{Code|$database}} exists, or a resource located at {{Code|$path}} in this database. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:exists("DB")}} returns {{Code|true}} if the database {{Code|DB}} exists. | ||
+ | * {{Code|db:exists("DB", "resource")}} returns {{Code|true}} if {{Code|resource}} exists in this database. | ||
+ | |} | ||
+ | |||
+ | ==db:type== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:type( | ||
+ | $database as xs:string, | ||
+ | $path as xs:string | ||
+ | ) as xs:string</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Returns the type ({{Code|xml}}, {{Code|binary}}, {{Code|value}}) of a resource in a {{Code|$database}} at the specified {{Code|$path}}. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:type("DB", "factbook.xml")}} returns {{Code|true}} if the specified resource is an XML document. | ||
+ | |} | ||
+ | |||
+ | ==db:content-type== | ||
+ | |||
+ | {| width='100%' | ||
+ | |- valign="top" | ||
+ | | width='120' | '''Signature''' | ||
+ | |<pre>db:content-type( | ||
+ | $database as xs:string, | ||
+ | $path as xs:string | ||
+ | ) as xs:string</pre> | ||
+ | |- valign="top" | ||
+ | | '''Summary''' | ||
+ | |Retrieves the content-type of a resource in a {{Code|$database}} at the specified {{Code|$path}}.<br/>The file extension is used to recognize the content-type of a resource stored in the database. {{Code|application/xml}} will be returned for any XML document stored in the database, regardless of its file name extension. | ||
+ | |- valign="top" | ||
+ | | '''Errors''' | ||
+ | |{{Error|open|#Errors}} the addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | | '''Examples''' | ||
+ | | | ||
+ | * {{Code|db:content-type("DB", "docs/doc01.pdf")}} returns {{Code|application/pdf}}. | ||
+ | * {{Code|db:content-type("DB", "docs/doc01.xml")}} returns {{Code|application/xml}}. | ||
+ | * {{Code|db:content-type("DB", "docs/doc01")}} returns {{Code|application/xml}}, if {{Code|db:is-xml("DB", "docs/doc01")}} returns {{Code|true}}. | ||
+ | |} | ||
+ | |||
+ | =Errors= | ||
+ | |||
+ | {| class="wikitable" width="100%" | ||
+ | ! width="110"|Code | ||
+ | | Description | ||
+ | |- valign="top" | ||
+ | |{{Code|args}} | ||
+ | |The number of specified inputs and paths differs. | ||
+ | |- valign="top" | ||
+ | |{{Code|conflict}} | ||
+ | |Multiple update operations point to the same target. | ||
+ | |- valign="top" | ||
+ | |{{Code|lock}} | ||
+ | |A database cannot be updated because it is opened by another process. | ||
+ | |- valign="top" | ||
+ | |{{Code|mainmem}} | ||
+ | |The addressed database is not ''persistent'' (stored on disk). | ||
+ | |- valign="top" | ||
+ | |{{Code|name}} | ||
+ | |The name of the specified database is invalid. | ||
+ | |- valign="top" | ||
+ | |{{Code|no-backup}} | ||
+ | |No backup exists for a database. | ||
+ | |- valign="top" | ||
+ | |{{Code|node}} | ||
+ | |The referenced XML node is no [[#Database Nodes|database node]], i.e. it is neither stored in a database nor represented as database fragment. | ||
+ | |- valign="top" | ||
+ | |{{Code|no-index}} | ||
+ | |The database lacks an index structure required by the called function. | ||
+ | |- valign="top" | ||
+ | |{{Code|open}} | ||
+ | |The addressed database does not exist or could not be opened. | ||
+ | |- valign="top" | ||
+ | |{{Code|option}} | ||
+ | |The specified option is unknown. | ||
+ | |- valign="top" | ||
+ | |{{Code|path}} | ||
+ | |The specified database path is invalid. | ||
+ | |- valign="top" | ||
+ | |{{Code|property}} | ||
+ | |The specified database property is unknown. | ||
+ | |- valign="top" | ||
+ | |{{Code|range}} | ||
+ | |The addressed database ID or PRE value is out of range. | ||
+ | |- valign="top" | ||
+ | |{{Code|target}} | ||
+ | |Path points to an invalid target. | ||
|} | |} | ||
− | [[ | + | =Changelog= |
+ | |||
+ | ;Version 10 | ||
+ | * Added: {{Function||db:get}}, {{Function||db:put}}, {{Function||db:type}}. | ||
+ | * Added: [[#Backups|Backups]]: Support for general data ([[User Management|registered users]], [[Job Module#Services|scheduled services]] and [[Store Module|key-value stores]]). | ||
+ | * Updated: {{Function||db:get}}, {{Function||db:get-id}}, {{Function||db:get-pre}} renamed (before: {{Code|db:open}}, {{Code|db:open-id}}, {{Code|db:open-pre}}) | ||
+ | * Updated: {{Function||db:put}} renamed (before: {{Code|db:replace}}); function signature aligned with {{Function||db:add}} (second and third argument swapped). | ||
+ | * Updated: {{Function||db:put-binary}} renamed (before: {{Code|db:store}}); function signature aligned with {{Function||db:add}} (second and third argument swapped). | ||
+ | * Updated: {{Function||db:get-binary}} renamed (before: {{Code|db:retrieve}}). | ||
+ | * Updated: {{Function||db:backups}}, {{Function||db:create-backup}}: Options added. | ||
+ | * Removed: {{Code|db:is-raw}}, {{Code|db:is-raw}} (new: {{Function||db:type}}). | ||
+ | |||
+ | ;Version 9.3 | ||
+ | * Added: {{Function||db:alter-backup}} | ||
+ | * Updated: {{Code|db:open-id}}, {{Code|db:open-pre}}: support for multiple integers | ||
+ | |||
+ | ;Version 9.2 | ||
+ | * Added: {{Function||db:dir}} | ||
+ | * Updated: {{Function||db:add}}: {{Code|$path}} allow empty path argument | ||
+ | |||
+ | ;Version 9.0 | ||
+ | * Added: {{Function||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: {{Function||db:property}} | ||
+ | |||
+ | ;Version 8.4 | ||
+ | * Updated: {{Function||db:create}}, {{Function||db:add}}, {{Code|db:replace}}: support for {{Code|ADDCACHE}} option. | ||
+ | * Added: {{Function||db:token}} | ||
+ | |||
+ | ;Version 8.3 | ||
+ | * Updated: {{Function||db:list-details}}: attributes with name of database and date of backup added to results. | ||
+ | * Updated: {{Function||db:backups}} now include attributes with name of database and date of backup. | ||
+ | * Updated: {{Function|Database|Value Indexes}}: raise error if no index exists. | ||
+ | |||
+ | ;Version 8.2 | ||
+ | * Added: {{Function||db:output-cache}} | ||
+ | * Removed: db:event | ||
+ | |||
+ | ;Version 7.9 | ||
+ | * Updated: parsing options added to {{Function||db:create}}, {{Function||db:add}} and {{Code|db:replace}}. | ||
+ | * Updated: allow {{Option|UPDINDEX}} if {{Code|$all}} is {{Code|true}}. | ||
+ | |||
+ | ;Version 7.8.2 | ||
+ | * Added: {{Function||db:alter}}, {{Function||db:copy}}, {{Function||db:create-backup}}, {{Function||db:drop-backup}}, {{Function||db:restore}} | ||
+ | |||
+ | ;Version 7.8 | ||
+ | * Removed: db:fulltext (use {{Function|Full-Text|ft:search}} instead) | ||
+ | |||
+ | ;Version 7.7 | ||
+ | * Added: {{Function||db:export}}, {{Function||db:name}}, {{Function||db:path}} | ||
+ | * Updated: {{Code|$options}} argument added to {{Function||db:create}} and {{Function||db:optimize}}. | ||
+ | * Updated: the functions no longer accept [[#Database Nodes|database nodes]] as reference. Instead, the name of a database must now be specified. | ||
+ | |||
+ | ;Version 7.6 | ||
+ | * Updated: {{Function||db:create}}: allow more than one input and path. | ||
+ | |||
+ | ;Version 7.5 | ||
+ | * Updated: {{Function||db:add}}: input nodes will be automatically converted to document nodes | ||
+ | * Added: {{Function||db:backups}} | ||
+ | * Added: {{Function||db:create}} | ||
+ | * Added: {{Function||db:drop}} | ||
+ | |||
+ | ;Version 7.3 | ||
+ | * Added: {{Function||db:flush}} | ||
+ | |||
+ | ;Version 7.2.1 | ||
+ | * Added: {{Function||db:text-range}}, {{Function||db:attribute-range}}, {{Function||db:output}} | ||
+ | |||
+ | ;Version 7.1 | ||
+ | * Added: {{Function||db:list-details}}, {{Function||db:content-type}} | ||
+ | * Updated: {{Function||db:info}}, {{Function||db:system}}, {{Code|db:retrieve}} | ||
+ | |||
+ | ;Version 7.0 | ||
+ | * Added: {{Function||db:exists}}, {{Code|db:retrieve}}, {{Code|db:store}}, {{Code|db:is-raw}}, {{Code|db:is-xml}} | ||
+ | * Updated: {{Function||db:list}}, {{Code|db:open}}, {{Function||db:add}} |
Latest revision as of 23:07, 1 December 2023
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.
Contents
Conventions[edit]
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[edit]
In BaseX, two internal representations exist for XML nodes:
1. Database nodes are:
- stored in a persistent database on disk;
- nodes of a document that has been generated temporarily with
fn:doc
,fn:parse-xml
and other functions; or - the result of a main-memory update.
2. Fragments are similar to DOM structures. They are created when XQuery node constructors are used (<a/>
, element a { }
, etc.).
Fragments require less memory for small XML structures, but database nodes are more efficient for larger amounts of data. Fragments nodes can be converted to database nodes by applying a main-memory update with an empty body to a node:
<xml>hello world</xml> update { }
Updating Functions[edit]
Various functions in this module are updating. Updating functions will not be immediately executed, but queued on the Pending Update List, and processed after the remaining query has been evaluated. This means that the order in which the functions are specified in the query often does not reflect the order in which they will eventually be executed.
General Functions[edit]
db:system[edit]
Signature | 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[edit]
Signature | 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 SHOW OPTIONS command returns similar output.
|
Errors | option : the specified option is unknown.
|
Examples |
|
db:info[edit]
Signature | db:info( $database as xs:string ) as element(database) |
Summary | Returns meta information on the specified $database . The output is similar to the INFO DB command.
|
Errors | open : the addressed database does not exist or could not be opened.
|
db:property[edit]
Signature | db:property( $database 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 specified $database . The available properties are the ones returned by db:info .
|
Errors | property : the specified property is unknown.
|
Examples |
|
db:list[edit]
Signature | db:list( $database as xs:string := (), $path as xs:string := () ) as xs:string* |
Summary | Without arguments, the names of all databases are returned that are accessible to the current user. If $database is specified, paths to all resources of this database are returned. The results can be restricted to resources starting with the specified $path .
|
Errors | open : the addressed database does not exist or could not be opened.
|
Examples |
|
db:list-details[edit]
Signature | db:list-details( $database as xs:string := (), $path as xs:string := () ) as element()* |
Summary | Without arguments, an element is returned for each database that is accessible to the current user:
If
|
Errors | open : the addressed database does not exist or could not be opened.
|
Examples |
|
db:dir[edit]
Signature | db:dir( $database as xs:string, $path as xs:string ) as element()* |
Summary | Returns metadata on all directories and resources of a $database in the specified $path . Two types of elements are returned:
The directories are not stored in the internal database layout. 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 |
|
Read Operations[edit]
db:get[edit]
Signature | db:get( $database as xs:string, $path as xs:string := () ) as document-node()* |
Summary | Returns all documents from the specified $database , or only documents matching the specified $path .
|
Errors | open : the addressed database does not exist or could not be opened.
|
Examples |
|
db:get-pre[edit]
Signature | db:get-pre( $database as xs:string, $values as xs:integer* ) as node()* |
Summary | Returns all nodes from a $database with the specified PRE values in distinct document order.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:get-id[edit]
Signature | db:get-id( $database as xs:string, $values as xs:integer* ) as node()* |
Summary | Returns all nodes from a $database with the specified ID $values in distinct document order.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:get-binary[edit]
Signature | db:get-binary( $database as xs:string, $path as xs:string ) as item() |
Summary | Returns a map with the paths and binary items of all resources in the specified $database . A single xs:base64Binary item is returned if a $path is specified. All items are lazy, i.e., the actual data will only be retrieved if it is processed.
|
Errors | open : the addressed database does not exist or could not be opened.mainmem : the database is not persistent (stored on disk).
|
Examples |
|
db:get-value[edit]
Signature | db:get-value( $database as xs:string, $path as xs:string ) as item()* |
Summary | Returns a map with the paths and values of all resources in the specified $database . A single value is returned if a $path is specified.
|
Errors | open : the addressed database does not exist or could not be opened.mainmem : the database is not persistent (stored on disk).
|
Examples |
|
db:node-pre[edit]
Signature | db:node-pre( $nodes as node()* ) as xs:integer* |
Summary | Returns the PRE values of the specified $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-id[edit]
Signature | db:node-id( $nodes as node()* ) as xs:integer* |
Summary | Returns the ID values of the specified $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:export[edit]
Signature | db:export( $database as xs:string, $path as xs:string, $options as map(*)? := map { } ) as empty-sequence() |
Summary | Exports the specified $database to the specified file $path . Existing files will be overwritten.The $options argument contains serialization parameters (see fn:serialize).
|
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 code can be used to export parts of the database: let $target := '/home/john/xml/target'
for $doc in db:get('DB', 'collection')
let $path := $target || db:path($doc)
return (
file:create-dir(file:parent($path)),
file:write($path, $doc)
)
|
Value Indexes[edit]
db:text[edit]
Signature | db:text( $database as xs:string, $values as xs:string* ) as text()* |
Summary | Returns all text nodes of a $database that match one of the specified $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-range[edit]
Signature | db:text-range( $database as xs:string, $min as xs:string, $max as xs:string ) as text()* |
Summary | Returns all text nodes of a $database whose values are larger than or equal to $min and smaller than or equal to $max 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:attribute[edit]
Signature | db:attribute( $database as xs:string, $values as xs:string*, $name as xs:string := () ) as attribute()* |
Summary | Returns all attribute nodes of a $database that match one of the specified $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-range[edit]
Signature | db:attribute-range( $database as xs:string, $min as xs:string, $max as xs:string, $name as xs:string := () ) as attribute()* |
Summary | Returns all attributes of a $database whose values 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:token[edit]
Signature | db:token( $database as xs:string, $tokens as xs:string*, $name as xs:string := () ) as attribute()* |
Summary | Returns all attribute nodes of a $database 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 |
|
Updates[edit]
All functions in this section are Updating Functions.
db:create[edit]
Signature | db:create( $database as xs:string, $inputs as item()* := (), $paths as xs:string* := (), $options as map(*)? := map { } ) as empty-sequence() |
Summary | Creates a new $database and adds the supplied $inputs to the specified $paths :
|
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:add[edit]
Signature | db:add( $database as xs:string, $input as item(), $path as xs:string? := (), $options as map(*)? := map { } ) as empty-sequence() |
Summary | Adds the specified $input to a $database with the specified $path :
|
Errors | open : the addressed database does not exist or could not be opened.
|
Examples |
|
db:put[edit]
Signature | db:put( $database as xs:string, $input as item(), $path as xs:string, $options as map(*)? := map { } ) as empty-sequence() |
Summary | Replaces a resource, specified by $path , in a $database with the contents of $input , or adds it as a new resource:
|
Errors | open : the addressed database does not exist or could not be opened.target : the path points to a directory.
|
Examples |
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:put('db', doc($path), $file)
|
db:put-binary[edit]
Signature | db:put-binary( $database as xs:string, $input as item(), $path as xs:string ) as empty-sequence() |
Summary | Stores a binary resource specified by $input in a $database at the specified $path . Existing resources are overwritten.
|
Errors | open : the addressed database does not exist or could not be opened.mainmem : the database is not persistent (stored on disk).
|
Examples |
let $db := 'db'
let $src-path := 'src/'
let $trg-path := 'trg/'
for $src in db:list($db, $src-path)
where db:type($db, $src) = 'binary'
let $trg := $trg-path || substring-after($src, $src-path)
return db:put-binary($db, db:get-binary($db, $src), $trg)
|
db:put-value[edit]
Signature | db:put-value( $database as xs:string, $input as item()*, $path as xs:string ) as empty-sequence() |
Summary | Stores an $input value in a $database at the specified $path . Existing resources are overwritten. The value can be an arbitrary sequence of atomic items, nodes, maps, and arrays.
|
Errors | open : the addressed database does not exist or could not be opened.mainmem : the database is not persistent (stored on disk).
|
Examples |
db:put-value(
'factbook',
map:merge(
for $country in db:get('factbook')//country
return map:entry($country/@name, $country//city/name ! string())
),
'cities'
)
|
db:delete[edit]
Signature | db:delete( $database as xs:string, $path as xs:string ) as empty-sequence() |
Summary | Deletes resource(s), specified by $path , from the specified $database .
|
Errors | open : the addressed database does not exist or could not be opened.path : the specified path is invalid.
|
Examples |
|
db:copy[edit]
Signature | db:copy( $database as xs:string, $new-name as xs:string ) as empty-sequence() |
Summary | Creates a copy of $database , which will be called $new-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[edit]
Signature | db:alter( $database as xs:string, $new-name as xs:string ) as empty-sequence() |
Summary | Renames a $database to $new-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:optimize[edit]
Signature | db:optimize( $database as xs:string, $all as xs:boolean? := false(), $options as map(*)? := map { } ) as empty-sequence() |
Summary | Optimizes the metadata and indexes of a $database .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:rename[edit]
Signature | db:rename( $database as xs:string, $source as xs:string, $target as xs:string ) as empty-sequence() |
Summary | Moves all resources(s) of a $database , 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:flush[edit]
Signature | db:flush( $database as xs:string ) as empty-sequence() |
Summary | Explicitly flushes the buffers of a $database . 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.
|
db:drop[edit]
Signature | db:drop( $database as xs:string ) as empty-sequence() |
Summary | Drops a $database 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 |
|
Backups[edit]
All functions in this section except for db:backups
are Updating Functions
.
db:create-backup[edit]
Signature | db:create-backup( $database as xs:string, $options as map(*)? := map { } ) as empty-sequence() |
Summary | Creates a backup of a $database . If no name is supplied, general data will be backed up. The following $options are available:
|
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:drop-backup[edit]
Signature | db:drop-backup( $name as xs:string ) as empty-sequence() |
Summary | Drops all backups of the database with the specified $name . If the name ends with a timestamp, only the specified backup file will be deleted. If no name is supplied, backups with general data are addressed.
|
Errors | backup : No backup file found.name : invalid database name.conflict : the same database was addressed more than once.
|
Examples |
|
db:alter-backup[edit]
Signature | db:alter-backup( $name as xs:string, $new-name as xs:string ) as empty-sequence() |
Summary | Renames all backups of the database with the specified $name to $new-name . If the name ends with a date, only the specified backup file will be renamed.
|
Errors | backup : No backup file found.name : invalid database name.conflict : the same database was addressed more than once.
|
Examples |
|
db:restore[edit]
Signature | 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. If no name is supplied, general data will be restored. If general data is restored, it will only be available after BaseX has been restarted.
|
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:backups[edit]
Signature | db:backups( $database as xs:string := () ) as element(backup)* |
Summary | Returns an element sequence containing all available database backups with timestamp, file size and comment. If a $database is specified, the sequence will be restricted to the backups matching this database.
|
Examples |
|
Helper Functions[edit]
db:name[edit]
Signature | 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[edit]
Signature | 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[edit]
Signature | db:exists( $database as xs:string, $path as xs:string := () ) as xs:boolean |
Summary | Checks if a $database exists, or a resource located at $path in this database.
|
Examples |
|
db:type[edit]
Signature | db:type( $database as xs:string, $path as xs:string ) as xs:string |
Summary | Returns the type (xml , binary , value ) of a resource in a $database at the specified $path .
|
Errors | open : the addressed database does not exist or could not be opened.
|
Examples |
|
db:content-type[edit]
Signature | db:content-type( $database as xs:string, $path as xs:string ) as xs:string |
Summary | Retrieves the content-type of a resource in a $database at the specified $path .The file extension is used to recognize the content-type of a resource stored in the database. 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 |
|
Errors[edit]
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[edit]
- Version 10
- Added:
db:get
,db:put
,db:type
. - Added: Backups: Support for general data (registered users, scheduled services and key-value stores).
- Updated:
db:get
,db:get-id
,db:get-pre
renamed (before:db:open
,db:open-id
,db:open-pre
) - Updated:
db:put
renamed (before:db:replace
); function signature aligned withdb:add
(second and third argument swapped). - Updated:
db:put-binary
renamed (before:db:store
); function signature aligned withdb:add
(second and third argument swapped). - Updated:
db:get-binary
renamed (before:db:retrieve
). - Updated:
db:backups
,db:create-backup
: Options added. - Removed:
db:is-raw
,db:is-raw
(new:db:type
).
- Version 9.3
- Added:
db:alter-backup
- Updated:
db:open-id
,db:open-pre
: support for multiple integers
- Version 9.2
- Version 9.0
- Added:
db:option
- Updated: db:output renamed to
update:output
, db:output-cache renamed toupdate:cache
- Updated: error codes updated; errors now use the module namespace
- Version 8.6
- Added:
db:property
- 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
- Added:
db:output-cache
- Removed: db:event
- Version 7.9
- Updated: parsing options added to
db:create
,db:add
anddb:replace
. - Updated: allow
UPDINDEX
if$all
istrue
.
- Version 7.8.2
- Added:
db:alter
,db:copy
,db:create-backup
,db:drop-backup
,db:restore
- Version 7.8
- Removed: db:fulltext (use
ft:search
instead)
- Version 7.7
- Added:
db:export
,db:name
,db:path
- Updated:
$options
argument added todb:create
anddb:optimize
. - Updated: the functions no longer accept database nodes as reference. Instead, the name of a database must now be specified.
- Version 7.6
- Updated:
db:create
: allow more than one input and path.
- Version 7.5
- Updated:
db:add
: input nodes will be automatically converted to document nodes - Added:
db:backups
- Added:
db:create
- Added:
db:drop
- Version 7.3
- Added:
db:flush
- Version 7.2.1
- Added:
db:text-range
,db:attribute-range
,db:output
- Version 7.1
- Added:
db:list-details
,db:content-type
- Updated:
db:info
,db:system
,db:retrieve
- Version 7.0