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Text replacement - "</syntaxhighlight>" to "</pre>"
In addition, custom stores can be read and written. Custom stores have filenames with the pattern {{Code|store-NAME.basex}}. The implicit write of the standard store at shutdown time will be disabled if a custom store is used.
Functions of this module are non-deterministic nondeterministic and side-effecting: Updates will immediately be visible, and a repeated call of the same function may yield different results if the contents of the store have changed.
=Conventions=
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:get|( $key as xs:string|) as item()*}}<br/ pre>|-valign="top"
|'''Summary'''
|Retrieves an entry from the store with the given {{Code|$key}}. If the addressed entry does not exist, an empty sequence is returned.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:put|( $key as xs:string, $value as item()*|) as empty-sequence()}}<br/ pre>|-valign="top"
|'''Summary'''
|Stores an entry with the given {{Code|$key}} and {{Code|$value}} in the store:
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:get-or-put|( $key as xs:string, $put as function(*)) as item()*|item()*}}<br/ pre>|-valign="top"
|'''Summary'''
|Retrieves an entry from the store with the given {{Code|$key}}. The {{Code|$put}} function will only be invoked if the entry does not exist, and its result will be stored and returned instead.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:remove|( $key as xs:string|) as empty-sequence()}}<br/ pre>|-valign="top"
|'''Summary'''
|Removes an entry with the given {{Code|$key}} from the store. No error will be raised if an addressed entry does not exist.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:keys||() as xs:string*}}</pre>|-valign="top"
|'''Summary'''
|Lists the names of all keys.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:clear||() as empty-sequence()}}<br/ pre>|-valign="top"
|'''Summary'''
|Resets the store by removing all its entries.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|store:read||empty-sequence()}}<br/ pre>{{Func|store:read|( $name as xs:string|? := ()) as empty-sequence()}}</pre>|-valign="top"
|'''Summary'''
|Retrieves the standard store from disk, or a custom store if a {{Code|$name}} is supplied.
|-valign="top"
|'''Errors'''
|{{Error|io|#Errors}} The store could not be read.<br/>{{Error|name|#Errors}} The specified name is invalid.<br/>{{Error|not-found|#Errors}} A store with the specified name does not exist.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|store:write||empty-sequence()}}<br/ pre>{{Func|store:write|( $name as xs:string|? := ()) as empty-sequence()}}</pre>|-valign="top"
|'''Summary'''
|Writes the standard store to disk, or to a custom store file if a {{Code|$name}} is supplied. If the standard store is empty, the store file will be deleted.
|-valign="top"
|'''Errors'''
|{{Error|io|#Errors}} The store could not be written.<br/>{{Error|name|#Errors}} The specified name is invalid.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:list||() as xs:string*}}</pre>|-valign="top"
|'''Summary'''
|Lists the names of all custom stores.
{| width='100%'
|-valign="top"| width='120' | '''SignaturesSignature'''|{{Func|<pre>store:delete|( $name as xs:string|) as empty-sequence()}}</pre>|-valign="top"
|'''Summary'''
|Deletes a custom store from disk.
|-valign="top"
|'''Errors'''
|{{Error|name|#Errors}} The specified name is invalid.<br/>{{Error|not-found|#Errors}} A store with the specified name does not exist.
'''Use Case 1: Create/update a system configuration in a running BaseX server instance:
<syntaxhighlight pre lang="'xquery"'>
(: store an integer :)
store:put('version', 1),
(: serialize configuration to disk :)
store:write()
</syntaxhighlightpre>
The configuration can be requested by further operations, e.g. a client request:
<syntaxhighlight pre lang="'xquery"'>
store:get('version')
</syntaxhighlightpre>
The store will still be available if BaseX is restarted until it is cleared.
'''Use Case 2: Create index for fast lookup operations in the GUI:
<syntaxhighlight pre lang="'xquery"'>
let $map := map:merge(
for $country in db:openget('factbook')//country
for $religion in $country//religions
group by $religion
)
return store:put('religions', $map)
</syntaxhighlightpre>
A subsequent query can be used to access its contents:
<syntaxhighlight pre lang="'xquery"'>
store:get('religions')?Buddhism
</syntaxhighlightpre>
Note that the store will eventually be written to disk unless it is invalidated before closing the GUI.
! width="110"|Code
|Description
|-valign="top"
|{{Code|io}}
| The store could not be read or written.
|-valign="top"
|{{Code|name}}
| The specified name is invalid.
|-valign="top"
|{{Code|not-found}}
| A store with the specified name does not exist.
