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XMLA Service-Definition Keywords
Currently, the XMLA service-definition file enables you to specify only that all authorized data is exposed to XMLA
requests, as illustrated in the following example:
Service {*}
8.2.3 XMLA Security Considerations
Enabling access to data by means of XMLA opens up some security considerations that you need to address, for
example, the data you want to expose, who can start the XMLA service, and so on.
If you want to use XMLA to expose data to users and clients in SAP HANA XS, you need to bear in mind the
security considerations described in the following list:
● Data Access
●
Restrict user select authorization for data exposed by the XMLA service
● XMLA Statistical content
Restrict access to the URL/Path used to expose XMLA content in the Web browser, for example, using the
application-access file (.xsaccess)
8.2.4 Multidimensional Expressions (MDX)
Multidimensional Expressions (MDX) is a language you can use to query multidimensional data stored in OLAP
cubes.
MDX uses a multidimensional data model to enable navigation in multiple dimensions, levels, and up and down a
hierarchy. With MDX, you can access pre-computed aggregates at specified positions (levels or members) in a
hierarchy.
Note: MDX is an open standard. However, SAP has developed extensions to MDX that are designed to
enable faster and more efficient access to multidimensional data, for example, to serve specific SAP
HANA application requirements and to optimize the resultset for SAP HANA clients.
MDX is implicitly a hierarchy-based paradigm. All members of all dimensions must belong to a hierarchy. Even if
you do not explicitly create hierarchies in your SAP HANA data model, the SAP HANA modeler implicitly
generates default hierarchies for each dimension. All identifiers that are used to uniquely identify hierarchies,
levels and members in MDX statements (and metadata requests) embed the hierarchy name within the identifier.
In SAP HANA, the standard use of MDX is to access SAP HANA models (for example, analytical and attribute
views) that have been designed, validated and activated in the modeler in the SAP HANA studio. The studio
provides a graphical design environment that enables detailed control over all aspects of the model and its
language-context-sensitive runtime representation to users.
MDX in SAP HANA uses a runtime cube model, which usually consists of an analytical (or calculation) view that
represents data in which dimensions are modeled as attribute views. You can use the analytical view to specify
whether a given attribute is intended for display purposes only or for aggregation. The key attributes of attribute
views are linked to private attributes in an analytical view in order to connect the entities. One benefit of MDX in
SAP HANA is the native support of hierarchies defined for attribute views.
Note: MDX in SAP HANA includes native support of hierarchies defined for attribute views. SAP HANA
supports level-based and parent-child hierarchies and both types of hierarchies are accessible with MDX.
SAP HANA Developer Guide
Defining Web-based Data Access
P U B L I C
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