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See:
Description
Interface Summary | |
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StepFilterInterface | Provides modeling for steps that filter data. |
StepInterface | A thin top-level interface for all steps. |
Class Summary | |
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CompoundStep | Enables a user to group a set of steps together. |
Provides a set of modeled "step" operations that can be applied, in a particular order, to data items and business queries to modify the results of a query.
Steps
A step is an operation that can modify the results of a query by providing additional filtering or other capability to the query. Steps are usually used for modifying portions of an OLAP query by applying them to data items or the query itself.
Steps define a particular filtering function:
For OLAP information maps filtering functions can be:
- Data based filtering - filter on a particular value in a measure that is associated with a dimension or tuple.
- Rank filtering - filter by either top or bottom count, sum, or percentage on a particular value or values for the member of a particular dimension or a data item in a relational information map.
- Navigation filtering - drilling, expanding, or collapsing in a particular dimension or tuple.
- Member filtering - filter on a particular level for a hierarchy such as [CARS].[COLOR].[RED].
- Member Property filtering - filter on a particular value in a member property for a hierarchy.
- Time filtering -filter on a particular period, set of periods, number of periods, or range of periods for a TIME or DATE hierarchy.
How steps are applied:
Steps can be applied by using one of the following action types:
- StepFilterInterface.INITIAL_ACTION_TYPE - overrides previously defined steps.
- StepFilterInterface.APPEND_ACTION_TYPE - appends a step to the end of previous steps.
- StepFilterInterface.PREPEND_ACTION_TYPE - adds a step to the beginning of previous steps.
- StepFilterInterface.DIFFERENCE_ACTION_TYPE - finds the difference between the results of the previous steps and the results of this step.
- StepFilterInterface.INTERSECT_ACTION_TYPE - finds the intersection of the results of the previous steps and the results of this step.
- StepFilterInterface.UNION_ACTION_TYPE - finds the union of the results of the previous steps and the results of this step.
- StepFilterInterface.SPECIAL_ACTION_TYPE - primarily applies expand and collapse navigation functions to a data item.
For an example of how to apply a step to a data item or a business query and the resulting MDX, see Step Use Cases.
Compound steps
Steps can be applied to data items as simple steps or compound steps. The compound step brings the notion of parentheses to steps. Steps are ordered operations, and the compound step enables the user to group a set of steps together.
For example, (Blue Car Models with Sales GT 1M) and (Red Car Models with Sales GT 2M). Each compound step can contain any number of steps -- whether simple or compound.
The following is a brief description of how AND/OR is applied by step
- OR condition for filter is:
Filter( (Blue Car Models with Sales GT 1M) OR (Red Car Models with Sales GT2M) )
- OR condition for ranking is:
{TopCount(Blue Car Models Top 25), BottomCount(Blue Car Models Bottom 25))
- OR condition for navigation is
Union(Blue Car Models.children, Red Car Models.children)
- OR condition for a mixed steps of ranking and filter is:
Union(TopCount(Blue Car Models Top 25), Blue Car Model with Sales GT 1M) </li>
Except(TopCount (Blue Car Models Top 25), Blue Car Model with Sales GT 1M)
For an example of how to apply multiple filtering steps to a data item the resulting MDX, see Compound Step Use Cases.
BaseFilter
BaseFilter is an abstract class representing a step that filters. This is the superclass for each of the various kinds of filters that can be applied to a data item.
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