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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 supports the use of variables in MDX queries; the variables are a SAP-specific enhancement to
standard MDX syntax. You can specify values for all mandatory variables that are defined in SAP HANA studio to
various modeling entities. The following example illustrates how to declare SAP HANA variables and their values:
MDX
Select
From [MINI_C1_VAR]
Where [Measures].[M2_1_M3_CONV]
SAP VARIABLES [VAR_VAT] including 10,
[VAR_K2] including 112,
[VAR_TARGET_CURRENCY] including 'EUR',
14.3.3 MDX Functions
MDX in SAP HANA supports a variety of standard MDX functions.
Table 17: Supported MDX Functions
Function Description
Aggregate Returns a calculated value using the appropriate aggregate function, based on the
aggregation type of the member.
Ancestor Returns the ancestor of a member at a specified level or at a specific distance away
in the hierarchy.
Ancestors Returns a set of all ancestors of a member at a specified level or at a specific
distance away in the hierarchy.
Ascendants Returns the set of the ascendants of the member.
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SAP HANA Developer Guide
Using Database Client Interfaces