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This page is linked from the [[Getting Started]] Section.
The options listed on this page influence the way how database [[Commands|commands]] are executed and XQuery expressions are evaluated. Options are divided into [[#Global Options|'''global options''']], which are valid for all BaseX instances, and '''local options''', which are specific to a client or session. Values Two kinds of options are either ''strings'', ''numbers'' or ''booleans''.exist:
The {{Code|.basex}} * '''[[Configuration#Configuration FilesGlobal Options|configuration fileGlobal Options]] ''' are valid for all BaseX instances in the same JVM. This is parsed by every new local BaseX instanceparticularly relevant if you are working with the client/server architecture. It contains * '''Local options''' (all global options and, optionally, local options at the end of the fileremaining ones) are specific to a client or session.
Values of options are either ''strings'', ''numbers'' or ''booleans''. Options are ''static'' and not bound to a single operation (for example, the next command). Various ways exist to access and change options:
* The current value of an option can be requested with the {{Command|GET}} command. Local options can be changed via {{Command|SET}}. All values are ''static'': They stay valid until they are (all global options, except for {{Option|DEBUG}}, can only be changed once again by another operationat startup time). If an option is of type ''boolean'', and if no value is specified, its current value will be inverted. * The {{Code|.basex}} [[Configuration#Configuration Files|configuration file]] is parsed by every new local BaseX instance. It contains all global options. Local options can be specified at the end of the file after the {{Code|Local Options}} comment: <pre class="brush:perl"># General OptionsDEBUG = false... # Local OptionsCHOP = false</pre>
* Initial values for global options can also be specified via system properties, which can e.g. be passed on with the [http://docs.oracle.com/javase/1.4.2/docs/tooldocs/windows/java.html#options -D flag] on command line, or using [http://docs.oracle.com/javase/6/docs/api/java/lang/System.html#setProperty(java.lang.String,%20java.lang.String) System.setProperty()] before creating a BaseX instance. The specified keys need to be prefixed with {{Code|org.basex.}}. An example:
<string>-Dorg.basex.CHOP=false</string>
</array>
</pre>
 
* In a [[Web Application]], the default can be adjusted in the {{Code|web.xml}} file as follows:
 
<pre class="brush:xml">
<context-param>
<param-name>org.basex.chop</param-name>
<param-value>false</param-value>
</context-param>
</pre>
===LOGPATH===
 
{{Mark|Updated with Version 8.5}}:
{| width='100%'
|}
===GLOBALLOCKFAIRLOCK=== {{Mark|Introduced with Version 8.6:}}
{| width='100%'
|-
| width='120' | '''Signature'''
|{{Code|GLOBALLOCK FAIRLOCK [boolean]}}
|-
| '''Default'''
|-
| '''Summary'''
|Controls Defines the locking strategy:* By default, non-fair is used. Read transactions will be favored, and transactions that access no databases can be evaluated even if local the limit of parallel transactions (database) or global specified via {{Option|PARALLEL}} has been reached. This prevents update operations from blocking all other requests (processfor example, the DBA can further be used to see which jobs are running, even if the queue is full) .* If fair locking is enabled, read and write transactions will be treated equally (first in, first out). This avoids starvation of update operations, and it should be used for managing read and write if the prompt evaluation of update operations. The article on [[Transaction Management]] provides more details on concurrency controlis critical.
|}
===CACHETIMEOUT===
 
{{Mark|Introduced with Version 8.5:}}
{| width='100%'
|-
| '''Summary'''
|Represents a password, which is used for accessing the server or an HTTP service:
* The default value will be overwritten if a client specifies its own credentials.
* If the default value is empty, login will only be possible if the client specifies credentials.
===AUTHMETHOD===
 
{{Mark|Updated with Version 8.5}}: {{Code|custom}} value added.
{| width='100%'
|-
| '''Summary'''
|Denotes the maximum allowed number of parallel [[Transaction Management|transactions]]:* If {{Option|FAIRLOCK}} is enabled, the number of parallel transactions will never exceed the specified value.<br/>Note * If the option is disabled (which is the default), the limit only applies to transactions that a access databases.* The main reason for allowing parallel operations is to prevent slow transactions from blocking all other operations. A higher number of parallel operations may increase disk activity and thus slow down queries. In some cases, a single transaction may even give you better results than any parallel activity. The main reason for allowing parallel operations is to prevent slow transactions from blocking all other operations.
|}
==HTTP Services==
If BaseX is run as web servlet, the Most HTTP options must be specified are defined in the {{Code|jetty.xml}} and {{Code|web.xml}} configuration files in the <code>[https://github.com/BaseXdb/basex/tree/master/basex-api/src/main/webapp/WEB-INF webapp/WEB-INF]</code> directory and . Some additional BaseX-specific options exist that will be set before the {{Code|jetty.xml}} and {{Code|web.xml}} configuration files.server is started:
===WEBPATH===
|}
===CACHERESTXQPARSERESTXQ=== {{Mark|Introduced with Version 8.6}}: replacing {{Code|CACHERESTXQ}}.
{| width='100%'
|-
| width='120' | '''Signature'''
|{{Code|CACHERESTXQPARSERESTXQ}}
|-
| '''Default'''
|{{Code|false3}}
|-
| '''Summary'''
|Disables Timeout after which the timestamp check when RESTXQ directory will be parsed for changes:* If {{Code|0}} is specified, the directory will be parsed every time a RESTXQ function is called.* A positive value defines the idle time in seconds after which parsing will be enforced. The default value is {{Code|3}}: Changes in the RESTXQ directory will be detected after 3 seconds without RESTXQ filesfunction calls.* Monitoring is completely disabled if a negative value is specified.  See [[RESTXQ#Preliminaries|RESTXQ Preliminaries]] for more details.
|}
|-
| '''Summary'''
|If this option is turned on, new databases will be exclusively created in main memory. :* Most queries will be evaluated faster in main -memory mode, but all data is lost if the BaseX instance in which the database was created is shut down. The value of this option * It is not possible to store binary resources in a main-memory database.* A main-memory database will be assigned once have no disk representation. However, it is possible to export the database via the {{Command|EXPORT}} command, and create a new databasefrom the exported file in a second step.* This option will not be available for [[Database Module#db:create|db:create]], and cannot because the database would not be changed accessible anymore after thatdatabase creation, i. e., outside the query scope.
|}
|-
| '''Summary'''
|Defines a [[Parsers|parser]] for importing new files to the database. Currently, 'Available parsers are {{Code|XML'}}, '{{Code|JSON'}}, '{{Code|CSV'}}, '{{Code|TEXT'}}, 'and {{Code|HTML' are available as parsers}}. HTML will be parsed as normal XML files if [http://home.ccil.org/~cowan/XML/tagsoup/ [Parsers#HTML_Parser|Tagsoup]] is not found in the classpath.
|}
|-
| '''Summary'''
|Specifies the way how HTML data will be parsed. Keys and values are delimited with <code>=</code>, and multiple options are delimited with <code>,</code>. The available options are described in the [[Parsers#Options|Parsers]] article.
|-
| '''Examples'''
|* <code>encoding=Shift-JIS,nons=true</code> parses the input as Sihft-JIS and suppresses namespaces.* <code>lexical=true</code> preserves comments.
|}
* The flag should be turned off if a document contains [[Full-Text#Mixed Content|mixed content]].
* The flag can also be turned off on [[Command-Line Options#BaseX Standalone|command line]] via <code>-w</code>.
* If the <code>xml:space="preserve"</code> attribute is attached to an element, chopping will be turned off for all descendant text nodes.  In the following example document, the whitespaces in the text nodes of the {{Code|text}} element will not be chopped:
<pre class="brush:xml">
<xml>
</xml>
</pre>
It is recommendable to additionally assign <code>indent=no</code> to the {{Option|SERIALIZER}} option; otherwise the serialized documents will automatically be indented.
|}
|This option affects the [[Indexes#Performance|construction]] of new value indexes. It controls the number of index build operations that are performed before writing partial index data to disk:
* The larger the assigned value is, the less splits will take place, and the more main memory will be required.
* By default, if the value is set to {{Code|0}}, some heuristics are applied, based on the current memory consumption. Usually, this works fine. If explicit garbage collection is disabled when running Java (e.g. via the JVM option {{Code|-XX:+DisableExplicitGC}}), you may need to choose a custom split size.
|}
XQUERY declare variable $GREETING external; $GREETING
</pre>
|}
 
===QUERYPATH===
 
{| width='100%'
|-
| width='120' | '''Signature'''
|{{Code|QUERYPATH [path]}}
|-
| '''Default'''
|''empty''
|-
| '''Summary'''
|Contains the path (''base URI'') to the executed query (default: ''empty''). This directory will be used to resolve relative paths to documents, query modules, and other resources addressed in a query.
|}
|-
| '''Summary'''
|This option controls inlining of XQuery functions:* The XQuery compiler inlines functions to speed up query evaluation. * Inlining will only take place if a function body is not too large (i.e., if it does not contain too many expressions). * With this option, this maximum number of expressions can be specified.<br/>* Function inlining can be turned off by setting the value to {{Code|0}}. * The limit can be locally overridden overwritten via the <code>[[XQuery_3.0XQuery Extensions#Annotationsbasex:inline|%basex:inline]]</code> annotation(follow the link to get more information on function inlining).
|}
| '''Examples'''
|
* <code>indent=no</code> : disables indentation of XML nodes (by default, this is enabled)
* <code>encoding=US-ASCII,omit-xml-declaration=no</code> : sets the encoding to {{Code|US-ASCII}} and prints the XML declaration.
* <code>item-separator=,,</code> : separates serialized items by a single comma.
=Changelog=
 
;Version 8.6
* Added: {{Option|FAIRLOCK}}, {{Option|PARSERESTXQ}}
* Removed: {{Code|GLOBALLOCK}} (exclusive use of database lock)
* Removed: {{Code|QUERYPATH}} (will now be internally assigned)
* Removed: {{Code|CACHERESTXQ}} (replaced with PARSERESTXQ)
;Version 8.5
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