XML for Analysis (XMLA) is an industry standard for data access in analytical systems, such as

online analytical processing Online analytical processing, or OLAP (), is an approach to answer multi-dimensional analytical (MDA) queries swiftly in computing. OLAP is part of the broader category of business intelligence, which also encompasses relational databases, re ...

(OLAP) and data mining. XMLA is based on other industry standards such as

XML Extensible Markup Language (XML) is a markup language and file format for storing, transmitting, and reconstructing arbitrary data. It defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. ...

SOAP Soap is a salt of a fatty acid used in a variety of cleansing and lubricating products. In a domestic setting, soaps are surfactants usually used for washing, bathing, and other types of housekeeping. In industrial settings, soaps are used ...

and

HTTP The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web, ...

. XMLA is maintained by XMLA Council with

Microsoft Microsoft Corporation is an American multinational corporation, multinational technology company, technology corporation producing Software, computer software, consumer electronics, personal computers, and related services headquartered at th ...

Hyperion Hyperion may refer to: Greek mythology * Hyperion (Titan), one of the twelve Titans * ''Hyperion'', a byname of the Sun, Helios * Hyperion of Troy or Yperion, son of King Priam Science * Hyperion (moon), a moon of the planet Saturn * ''Hyp ...

and

SAS Institute SAS Institute (or SAS, pronounced "sass") is an American multinational developer of analytics software based in Cary, North Carolina. SAS develops and markets a suite of analytics software ( also called SAS), which helps access, manage, anal ...

being the XMLA Council founder members.

History

The XMLA specification was first proposed by

as a successor for OLE DB for OLAP in April 2000. By January 2001 it was joined by

endorsing XMLA. The 1.0 version of the standard was released in April 2001, and in September 2001 the XMLA Council was formed. In April 2002 SAS joined Microsoft and Hyperion as founding member of XMLA Council. With time, more than 25 companies joined with their support for the standard.

API

XMLA consists of only two

methods.: execute and discover. It was designed in such a way to preserve simplicity.

Execute

Execute method has two parameters: * Command - command to be executed. It can be MDX, DMX or SQL. * Properties -

list of command properties such as Timeout, Catalog name, etc. The result of Execute command could be ''Multidimensional Dataset'' or ''Tabular Rowset''.

Discover

Discover method was designed to model all the discovery methods possible in OLEDB including various schema rowset, properties, keywords, etc. Discover method allows users to specify both what needs to be discovered and the possible restrictions or properties. The result of Discover method is a rowset.

Query language

XMLA specifies MDXML as the query language. In the XMLA 1.1 version, the only construct in MDXML is an MDX statement enclosed in the tag.

Example

Below is an example of XMLA Execute request with MDX query in command. SELECT Measures.MEMBERS ON COLUMNS FROM Sales FoodMart Multidimensional TupleFormat

Session management

XMLA has a notion of ''session state''. It is maintained through predefined ''

headers'' * BeginSession - to begin a new session * EndSession - to end existing session * UseSession - to use existing session. SessionId attribute previously returned for BeginSession should be used.

References

External links

XMLA resources and links
{{Data warehouse XML-based standards Online analytical processing Application programming interfaces