2.2.5.2.7 Cache Hierarchies
A cache hierarchy corresponds to one of the following entities in the OLAP source data (section 2.2.5.2.1) associated with an OLAP PivotCache (section 2.2.5.2):
Cache hierarchies are only present in OLAP PivotCaches and MUST NOT exist in a non-OLAP PivotCache.
The sequence of records that conforms to the PCDHIERARCHY rule (defined in section 2.1.7.38) specifies a cache hierarchy that corresponds to an OLAP hierarchy, an OLAP measure or an OLAP named set, as specified in the following table.
|
fMeasure field of BrtBeginPCDHierarchy |
fSet field of BrtBeginPCDHierarchy |
Meaning |
|---|---|---|
|
0 |
0 |
OLAP hierarchy |
|
0 |
1 |
OLAP named set |
|
1 |
0 |
OLAP measure |
The sequence of records that conforms to the PCDKPI rule (defined in section 2.1.7.38) specifies a cache hierarchy that corresponds to an OLAP KPI.
The association between a cache hierarchy and the corresponding OLAP entity in the OLAP source data (section 2.2.5.2.1) is specified by the stUnique field of the BrtBeginPCDHierarchy (section 2.4.146) record or by the stUnique field of the BrtBeginPCDKPI (section 2.4.148) record.
For a cache hierarchy that corresponds to an OLAP hierarchy, OLAP measure or OLAP named set, the cache hierarchy index is the zero-based index of a BrtBeginPCDHierarchy record in the BrtBeginPCDHierarchies (section 2.4.145) collection.
For a cache hierarchy that corresponds to an OLAP KPI, the cache hierarchy index is the n-based index of a BrtBeginPCDKPI record in the BrtBeginPCDKPIs (section 2.4.149) collection, where n is the number of BrtBeginPCDHierarchy records in the BrtBeginPCDHierarchies collection, as specified in section 2.1.7.38.
A cache field (section 2.2.5.2.2) can be associated with a cache hierarchy as specified by the ihdb field of the BrtBeginPCDField (section 2.4.136) record of the cache field.
A cache hierarchy that corresponds to an OLAP hierarchy represents one or more OLAP levels related via hierarchical relationships. For example, an OLAP hierarchy consisting of country/region, province, and city can be used to summarize national/regional, area, and municipal sales data. For a cache hierarchy that corresponds to an OLAP hierarchy, and is not a single field page hierarchy, each cache field (section 2.2.5.2.2) associated with the cache hierarchy corresponds to an OLAP level of the OLAP hierarchy or is a member property cache field.
A single field page hierarchy is a cache hierarchy that corresponds to an OLAP hierarchy in a PivotCache (section 2.2.5.2) that has a bVerCacheCreated field of the BrtBeginPivotCacheDef (section 2.4.168) less than 3 and has a PivotTable view (section 2.2.5.3) that has the associated pivot hierarchy (section 2.2.5.3.4) on the page axis (section 2.2.5.3.7.1). For a single field page hierarchy a single cache field is associated with the cache hierarchy.