Thursday, 22 May 2014

OBIEE 11g Concepts (II) – How Do Filters and Selection Steps Differ?


There are number of questions business users ask around OBIEE/OBIA implementations. Some of them are specific to functional stuff e.g.  #invoice on hold represents # hold invoices or # invoices items?  In addition some of the ambitious questions are around product features and basic product offerings e.g. what is difference between filter and selection steps?    How many different types of views OBIEE supports etc. 

This blog series is an attempt to give a simple layman definition of number of concepts or OBIEE 11g terminology /offering. In this blog I am covering differences between filters and selection steps. The definitions are extracted from Oracle Standard Product documentation.

Filters and Selection Steps

Filters and Selection Steps are used to limit the results that are displayed when an analysis is run, so that the results answer a particular question

Together with the columns that user selects for an analysis, filters and selection steps determine what the results contain. Based on the filters and selection steps, only those results that match the criteria are shown. For example, depending on the organization in which user work, you can use filters and selection steps to learn who are the top ten applicant sources, what are the work load is for a particular group of recruiters, the types of requisition have the fastest time to fill, and so on.
Another kind of filter, called a prompt, can apply to all items in a dashboard. Prompts can be used to complete selection steps and filters at run-time.

Oracle BI provides the Filters view and Selection Steps view, which user can add to an analysis to display any filters or selection steps applied to the analysis. Adding these views can help the user understand the information displayed in the analysis.

How Do Filters and Selection Steps Differ?

Filters and selection steps are applied on a column-level basis and provide two methods for limiting the data in an analysis. A filter is always applied to a column before any selection steps are applied. Steps are applied in their specified order. Filters and selection steps differ in various ways.

Filters

Filters can be applied directly to attribute columns and measure columns. Filters are applied before the query is aggregated and affect the query and thus the resulting values for measures.

For example, suppose that there is a list of members in which the aggregate sums to 100. Over time, more members meet the filter criteria and are filtered in, which increases the aggregate sum to 200.

Selection Steps

Selection steps are applied after the query is aggregated and affect only the members displayed, not the resulting aggregate values.

For example, suppose that you have a list of hierarchical members in which the aggregate sums to 100. If you remove one of the members using a selection step, then the aggregate sum remains at 100.

Attribute & Hierarchical Columns 

One can create selection steps for both attribute columns and hierarchical columns. Selection steps are per column and cannot cross columns. Because attribute columns do not have an aggregate member, the use of selection steps versus filters for attribute columns is not as distinctive as for hierarchical columns.

Measure Columns

While measure columns are displayed in the Selection Steps pane, you cannot create steps for them so steps do not affect them. Measures are used to create condition steps for attribute and hierarchical columns, such as Requisitions open for more than one year.

This blog series is an attempt to expand my blog reach to BI End User or Business Users along with BI Developers/Architects.

No comments:

Post a Comment