Commands

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Basics

String Syntax

The following lines contain some commands for creating a database, adding two documents to it and performing a query: 

CREATE DB test
ADD input.xml
ADD TO embedded.xml <root>embedded</root>
XQUERY count(//text())

If multiple commands are specified in a single line, they can be separated by semicolons.

XML Syntax

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The string syntax is limited when it comes to embedding XML snippets or specifying complex queries, This is why database commands can also be specified in XML. The syntax of the BaseX Markup Language. An example: 

<create-db name='test'><root>Text</root></create-db>

If multiple commands are specified, they are wrapped into a <commands/> root element: 

<commands>
  <create-db name='test'/>
  <add>input.xml</add>
  <add path='embedded.xml'><root>embedded</root></add>
  <xquery>count(//text())</xquery>
</commands>

Command Scripts

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Commands strings and XML scripts can also be stored to disk. If a file with .bxs as suffix is passed on to a BaseX instance or command, it will automatically be recognized and evaluated as a command script.

Glob Syntax

Some commands support the glob syntax to address more than one database or user. Question marks and asterisks can be used to match one or more characters, and commas can be used to separate multiple patterns. Some examples:

  • AB? addresses all names with the characters AB and one more character.
  • *AB addresses all names ending with the characters AB.
  • X*,Y*,Z* addresses all names starting with the characters X, Y, or Z.

Valid Names

Both database and user names must follow the same naming constraints. Valid names may contain letters, numbers, underscores and dashes. Names must have at least one character; they also should not be longer than 128 characters, although this is not enforced. A regular expression matching valid names is [-_a-zA-Z0-9]{1,128}.

Aliases

In all commands, the DB keyword can be replaced by DATABASE.

Database Operations

CREATE DB

Syntax CREATE DB [name] ([input])
XML Syntax    <create-db name='...'>([input])</create-db>
Permission CREATE
Summary Creates the database [name] with an optional [input] and opens it.
The input may either be a reference to a single XML document, a directory, a remote URL, or a string containing XML:
Errors The command fails if a database with the specified name is currently used by another process, if one of the documents to be added is not well-formed or if it cannot be parsed for some other reason.
Examples
  • CREATE DB input
    creates an empty database input.
  • CREATE DB xmark http://files.basex.org/xml/xmark.xml
    creates the database xmark, containing a single initial document called xmark.xml.
  • CREATE DATABASE coll /path/to/input
    creates the database coll with all documents found in the input directory.
  • SET INTPARSE false; CREATE DB input input.xml
    creates a database input with input.xml as initial document, which will be parsed with Java's default XML parser.
  • <create-db name='simple'><hello>Universe</hello></create-db>
    creates a database named simple with an initial document <hello>Universe</hello>.

OPEN

Template:Mark name and path are now specified as separate arguments.

Syntax OPEN [name] ([path])
XML Syntax    <open name='...' (path='...')/>
Permission READ
Summary Opens the database [name], optionally limited to the documents with the specified [path].
Errors The command fails if the specified database does not exist, is currently being updated by another process or cannot be opened for some other reason.

CHECK

Template:Mark can now be used to create empty databases.

Syntax CHECK [input]
XML Syntax    <check input='...'/>
Permission READ/CREATE
Summary This convenience command combines OPEN and CREATE DB: if a database with the name [input] exists, it is opened. Otherwise, a new database is created; if the specified input points to an existing resource, it is stored as initial content.
Errors The command fails if the addressed database could neither be opened nor created.

CLOSE

Syntax CLOSE
XML Syntax    <close/>
Permission READ
Summary Closes the currently opened database.
Errors The command fails if the database files could not be closed for some reason.

EXPORT

Syntax EXPORT [path]
XML Syntax    <export path='...'/>
Permission CREATE
Summary Exports all documents in the database to the specified [path], using the serializer options specified by the EXPORTER option.
Errors The command fails if no database is opened, if the target path points to a file or is invalid, if the serialization parameters are invalid, or if the documents cannot be serialized for some other reason.

CREATE INDEX

Syntax CREATE INDEX [TEXT|ATTRIBUTE|FULLTEXT]
XML Syntax    <create-index type='text|attribute|fulltext'/>
Permission WRITE
Summary Creates the specified database index.
Errors The command fails if no database is opened, if the specified index is unknown, or if indexing fails for some other reason.

DROP INDEX

Syntax DROP INDEX [TEXT|ATTRIBUTE|FULLTEXT]
XML Syntax    <drop-index type='text|attribute|fulltext'/>
Permission WRITE
Summary Drops the specified database index.
Errors The command fails if no database is opened, if the specified index is unknown, or if it could not be deleted for some other reason.

Administration

ALTER DB

Syntax ALTER DB [name] [newname]
XML Syntax    <alter-db name='...' newname='...'/>
Permission CREATE
Summary Renames the database specified by [name] to [newname]. [newname] must be a valid database name.
Errors The command fails if the target database already exists, if the source database does not exist or is currently locked, or if it could not be renamed for some other reason.
Examples
  • ALTER DB db tempdb
    renames the database db into tempdb.

DROP DB

Syntax DROP DB [name]
XML Syntax    <drop-db name='...'/>
Permission CREATE
Summary Drops the database with the specified [name]. The Glob Syntax can be used to address more than one database.
Errors The command fails if the specified database does not exist or is currently locked, or if the database could not be deleted for some other reason.

CREATE BACKUP

Syntax CREATE BACKUP [name]
XML Syntax    <create-backup name='...'/>
Permission CREATE
Summary Creates a zipped backup of the database specified by [name]. The backup file will be suffixed with the current timestamp and stored in the database directory. The Glob Syntax can be used to address more than one database.
Errors The command fails if the specified database does not exist, or if it could not be zipped for some other reason.
Examples
  • BACKUP db
    creates a zip archive of the database db (e.g. db-2011-04-01-12-27-28.zip) in the database directory.

RESTORE

Syntax RESTORE [name]
XML Syntax    <restore name='...'/>
Permission CREATE
Summary Restores a database with the specified [name]. The name may include the timestamp of the backup file.
Errors The command fails if the specified backup does not exist, if the database to be restored is currently locked, or if it could not be restored for some other reason.

DROP BACKUP

Syntax DROP BACKUP [name]
XML Syntax    <drop-backup name='...'/>
Permission CREATE
Summary Drops all backups of the database with the specified [name]. The Glob Syntax can be used to address more than one database.
Examples
  • DROP BACKUP abc*
    deletes the backups of all databases starting with the characters abc.

SHOW BACKUPS

Syntax SHOW BACKUPS
XML Syntax    <show-backups/>
Permission CREATE
Summary Shows all database backups.

COPY

Syntax COPY [name] [newname]
XML Syntax    <copy name='...' newname='...'/>
Permission CREATE
Summary Creates a copy of the database specified by [name]. [newname] must be a valid database name.
Errors The command fails if the target database already exists, or if the source database does not exist.

INFO DB

Syntax INFO DB
XML Syntax    <info-db/>
Permission READ
Summary Shows information on the currently opened database.
Errors The command fails if no database is opened.

INFO INDEX

Syntax INFO INDEX ([TAG|ATTNAME|PATH|TEXT|ATTRIBUTE|FULLTEXT])
XML Syntax    <info-index type='tag|attname|path|text|attribute|fulltext'/>
Permission READ
Summary Shows information on the existing index structures. The output can be optionally limited to the specified index.
Errors The command fails if no database is opened, or if the specified index is unknown.

INFO STORAGE

Syntax INFO STORAGE [start end] | [query]
XML Syntax    <info-storage>([query])</info-storage>
Permission READ
Summary Shows the internal main table of the currently opened database. An integer range or a query may be specified as argument.
Errors The command fails if no database is opened, or if one of the specified arguments is invalid.

Querying

LIST

Template:Mark name and path are now specified as separate arguments.

Syntax LIST ([name] ([path]))
XML Syntax    <list (name='...' (path='...'))/>
Permission NONE
Summary Lists all available databases. If [name] is specified, the resources of a database are listed. The output can be further restricted to the resources matching the specified [path].
Errors The command fails if the optional database cannot be opened, or if the existing databases cannot be listed for some other reason.

XQUERY

Syntax XQUERY [query]
XML Syntax    <xquery>[query]</xquery>
Permission depends on query
Summary Runs the specified [query] and prints the result.
Errors The command fails if the specified query is invalid.
Examples
  • XQUERY 1 to 10
    returns the sequence (1, 2, 3, 4, 5, 6, 7, 8, 9, 10).
  • SET RUNS 10; XQUERY 1 to 10
    runs the query 10 times, returns the result and prints the average execution time.
  • SET XMLPLAN true; XQUERY 1 to 10
    returns the result and prints the query plan as XML.

RETRIEVE

Syntax RETRIEVE [path]
XML Syntax    <retrieve path='...'/>
Permission READ
Summary Retrieves a raw file from the opened database at the specified [path].
Errors The command fails if no database is opened, if the source path is invalid or if the data cannot not be retrieved for some other reason.

FIND

Syntax FIND [query]
XML Syntax    <find>[query]</find>
Permission READ
Summary Builds and runs a query for the specified [query] terms. Keywords can be enclosed in quotes to look for phrases. The following modifiers can be used to further limit search:

= looks for exact text nodes
~ looks for approximate hits
@= looks for exact attribute values
@ looks for attributes

Errors The command fails if no database is opened.

CS

Syntax CS [query]
XML Syntax    <cs>[query]</cs>
Permission depends on query
Summary Evaluates the specified [query] and declares the resulting nodes as new context set. In subsequent queries, the context set will be available via the context item expression of XQuery (.).
Errors The command fails if no database is opened, if the specified query is invalid or if it does not return nodes of the currently opened database.

REPO INSTALL

Syntax REPO INSTALL [path]
XML Syntax    <repo-install path='...'/>
Permission CREATE
Summary Installs the package with path [path].
Errors The command fails in the following cases:
  • The package to be installed is not a xar file.
  • The package to be installed does not exist or is already installed.
  • The package descriptor is with invalid syntax.
  • The package to be installed depends on a package which is not installed.
  • The package is not supported by the current version of BaseX.
  • A component of the package is already installed as part of another package.

REPO LIST

Syntax REPO LIST
XML Syntax    <repo-list/>
Permission READ
Summary Lists all installed packages.

REPO DELETE

Syntax REPO DELETE [name]
XML Syntax    <repo-delete name='...'/>
Permission CREATE
Summary Deletes the package with name [name], optionally followed by a version.
Errors The command fails if the package to be deleted participates in a dependency.

Updates

ADD

Syntax ADD (TO [path]) [input]
XML Syntax    <add (path='...')>[input]</add>
Permission WRITE
Summary Adds the files, directory or XML string specified by [input] to the currently opened database at the specified [path].
[input] may either be a single XML document, a directory, a remote URL or a plain XML string. If the path denotes a directory, it needs to be suffixed with a slash (/).
Errors The command fails if no database is opened, if one of the documents to be added is not well-formed, or if it could not be parsed for some other reason.
Examples
  • ADD input.xml
    adds the file input.xml to the database.
  • ADD TO temp/one.xml input.xml
    adds input.xml to the database and moves it to temp/one.xml.
  • ADD TO target/ xmldir
    adds all files from the xmldir directory to the database in the target path.

DELETE

Syntax DELETE [path]
XML Syntax    <delete path='...'/>
Permission WRITE
Summary Deletes all documents from the currently opened database that start with the specified [path].
Errors The command fails if no database is opened.

RENAME

Syntax RENAME [path] [newpath]
XML Syntax    <rename path='...' newpath='...'/>
Permission WRITE
Summary Renames all document paths in the currently opened database that start with the specified [path]. The command may be used to either rename single documents or directories.
Errors The command fails if no database is opened, or if the target path is empty.
Examples
  • RENAME one.xml two.xml
    renames the document one.xml to two.xml.
  • RENAME / TOP
    moves all documents to a TOP root directory.

REPLACE

Syntax REPLACE [path] [input]
XML Syntax    <replace path='...'>[input]</replace>
Permission WRITE
Summary Replaces a document in the currently opened database, addressed by [path], with the file or XML string specified by [input], or adds it as a new document.
Errors The command fails if no database is opened, if the specified path points to a database directory, or if the input is not found.
Examples
  • REPLACE one.xml input.xml
    replaces the document one.xml with the contents of the file input.xml.
  • REPLACE top.xml <xml/>
    replaces the document top.xml with the document <xml/>.

STORE

Syntax STORE (TO [path]) [input]
XML Syntax    <store (path='...')>[input]</store>
Permission WRITE
Summary Stores a raw file in the opened database to the specified [path]. [input] may either be a file reference, a remote URL, or a plain string. If the path denotes a directory, it needs to be suffixed with a slash (/).
Errors The command fails if no database is opened, if the specified resource is not found, if the target path is invalid or if the data cannot not be written for some other reason.

OPTIMIZE

Syntax OPTIMIZE (ALL)
XML Syntax    <optimize/>
<optimize-all/>
Permission WRITE
Summary Optimizes the index structures, meta data and statistics of the currently opened database. If the ALL flag is specified, the internal database structures are completely rebuilt; this often leads to a reduction of the total database size.
Errors The command fails if no database is opened, or if the currently opened database is a main-memory instance.

FLUSH

Syntax FLUSH
XML Syntax    <flush/>
Permission WRITE
Summary Explicitly flushes the buffers of the currently opened database to disk. This command is applied if AUTOFLUSH has been set to false.
Errors The command fails if no database is opened.

Server Administration

SHOW DATABASES

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Syntax SHOW DATABASES
XML Syntax    <show-databases/>
Permission ADMIN
Summary Shows all databases that are opened in the current server instance.

SHOW SESSIONS

Syntax SHOW SESSIONS
XML Syntax    <show-sessions/>
Permission ADMIN
Summary Shows all sessions that are connected to the current server instance.

SHOW USERS

Syntax SHOW USERS (ON [database])
XML Syntax    <show-users (database='...')/>
Permission ADMIN
Summary Shows all users that are registered in the database. If a [database] is specified, local users are shown.
Errors The command fails if the optional database could not be opened.

KILL

Syntax KILL [target]
XML Syntax    <kill target='...'/>
Permission ADMIN
Summary Kills sessions of a user or an IP:port combination, specified by [target]. The Glob Syntax can be used to address more than one user.
Errors The command fails if a user tried to kill his/her own session.

CREATE EVENT

Syntax CREATE EVENT [NAME]
XML Syntax    <create-event name='...'/>
Permission ADMIN
Summary Creates the specified event.
Errors The command fails if event already exists.

SHOW EVENTS

Syntax SHOW EVENTS
XML Syntax    <show-events/>
Permission ADMIN
Summary Shows all events that have been registered in the database.

DROP EVENT

Syntax DROP EVENT [NAME]
XML Syntax    <drop-event name='...'/>
Permission ADMIN
Summary Drops the specified event.
Errors The command fails if the event doesn't exist.

User Management

CREATE USER

Syntax CREATE USER [name] ([password])
XML Syntax    <create-user name='...'>([password])</create-user>
Permission ADMIN
Summary Creates a user with the specified [name] and [password]. [name] must be a valid user name. The password must be a valid MD5 hash value. If no password is specified in the console mode, it is requested via standard input.
Errors The command fails if the specified user already exists, or if the password is no valid MD5 hash value.

ALTER USER

Syntax ALTER USER [name] ([password])
XML Syntax    <alter-user name='...'>([password])</alter-user>
Permission ADMIN
Summary Alters the [password] of the user specified by [name]. The password must be a valid MD5 hash value. If no password is specified in the console mode, it is requested via standard input.
Errors The command fails if the specified user does not exist, or if the password is no valid MD5 hash value.

DROP USER

Syntax DROP USER [name] (ON [database]):
XML Syntax    <drop-user name='...' (database='...')/>
Permission ADMIN
Summary Drops the user with the specified [name]. If a [database] is specified, the user is only dropped locally. The Glob Syntax can be used to address more than one database or user.
Errors The command fails if admin is specified as user name, if the specified user does not exist or is logged in, or if the optional database could not be opened for modification.

GRANT

Syntax GRANT [NONE|READ|WRITE|CREATE|ADMIN] (ON [database]) TO [user]
XML Syntax    <grant name='...' permission='none|read|write|create|admin' (database='...')/>
Permission ADMIN
Summary Grants the specified permission to the specified [user]. If a [database] is specified, the permissions are only granted locally. The Glob Syntax can be used to address more than one database or user.
Errors The command fails if admin is specified as user name, if the specified user does not exist, or if the optional database could not be opened for modification.
Examples
  • GRANT READ TO JoeWinson
    grants READ permission to the user JoeWinson.
  • GRANT WRITE ON Wiki TO editor*
    grants WRITE permissions on the Wiki database to all users starting with the characters editor*.

PASSWORD

Syntax PASSWORD ([password])
XML Syntax    <password>([password])</password>
Permission NONE
Summary Changes the [password] of the current user. The password must be a valid MD5 hash value. If no password is specified in the console mode, it is requested via standard input.
Errors The command fails if the password is no valid MD5 hash value.

General Commands

RUN

Syntax RUN [file]
XML Syntax    <run file='...'/>
Permission depends on input
Summary Evaluates the contents of [file] as XQuery expression. Since Version 7.4, if the file ends with the suffix .bxs, the file content will be evaluated as command script. This command can be used to run several commands in a single transaction.
Errors The command fails if the specified file does not exist, or if the retrieved input is invalid. It will be canceled as soon as one of the executed commands fails.
Examples
  • RUN query.xq
    will evaluated the specified file as XQuery expression
  • RUN commands.bxs
    will evaluated the specified file as command script

EXECUTE

Template:Mark

Syntax EXECUTE [input]
XML Syntax    <execute>[input]</execute>
Permission depends on input
Summary Evaluates the specified [input] as command script. This command can be used to run several commands in a single transaction.
Errors The command fails if the syntax of the specified input is invalid. It will be canceled as soon as one of the executed commands fails.
Examples
  • EXECUTE "create db db1; create db db2"
  • EXECUTE "<commands><create-db name='db1'/><create-db name='db2'/></commands>"
    both commands will create two databases db1 and db2 in a single transaction.

GET

Syntax GET [option]
XML Syntax    <get option='...'/>
Permission NONE
Summary Returns the current value of the Option specified via [key].
Errors The command fails if the specified option is unknown.

SET

Syntax SET [option] ([value])
XML Syntax    <set option='...'>([value])</set>
Permission NONE
Summary Sets the Option with the specified [key] to a new [value]. Only local options can be modified. If no value is specified, and if the value is boolean, it will be inverted.
Errors The command fails if the specified option is unknown or if the specified value is invalid.

INFO

Syntax INFO
XML Syntax    <info/>
Permission READ
Summary Shows global information.

HELP

Syntax HELP ([command])
XML Syntax    <help>([command])</help>
Permission NONE
Summary If [command] is specified, information on the specific command is printed; otherwise, all commands are listed.
Errors The command fails if the specified command is unknown.

EXIT

Syntax EXIT
XML Syntax    <exit/>
Permission NONE
Summary Exits the console mode.

Changelog

Version 7.4
Version 7.3
  • Added: XML Syntax added
  • Updated: CHECK can now be used to create empty databases.
  • Updated: Names and paths in OPEN and LIST are now specified as separate arguments.
Version 7.2.1
  • Updated: permissions for GET and SET changed from READ to NONE
Version 7.2
Version 7.1
  • Updated: KILL (killing sessions by specifying IP:port)
Version 7.0
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