Pentaho Analyzer supports many types of relative date filters, but in order to apply them for a given level, you need to define the format string used to construct MDX members for that level. This is because each data warehouse implementation may have a different date format and set of hierarchy levels.
Common Relative Date Filters
In the Steel Wheels sample data cube provided by Pentaho for evaluation and testing, the Month level uses abbreviated three-letter month names. Furthermore, the Month level sits under the Quarter level. In Steel Wheels, the format string for an MDX member from the Month level would look like this:
Some other common date formats:
- [yyyy] (Year)
- [yyyy].[q] (Quarter)
- [yyyy].[q].[M] (Month)
- [yyyy].[q].[M].[w] (Week)
- [yyyy].[q].[M].[w].[yyyy-MM-dd] (Day)
The Day line above also specifies a format to represent the entire date. Without this format, a simple [d] parameter would be difficult to put into context. For more information on date format strings, refer to the SimpleDateFormat page on the ICU Project site.
To setup relative date filtering, for each level, you need to do the following:
- In your Mondrian schema file, set the levelType XML attribute to TimeYears, TimeMonths, TimeQuarters, TimeWeeks or TimeDate
- Define the MDX date member format as an annotation with the name AnalyzerDateFormat.
Here is an example from the Pentaho sample data (Steel Wheels) Time dimension:
<Level name="Years" levelType="TimeYears" ... > <Annotations><Annotation name="AnalyzerDateFormat">[yyyy]</Annotation></Annotations> </Level> <Level name="Quarters" levelType="TimeQuarters" ... > <Annotations><Annotation name="AnalyzerDateFormat">[yyyy].['QTR'q]</Annotation></Annotations> </Level> <Level name="Months" levelType="TimeMonths" ... > <Annotations><Annotation name="AnalyzerDateFormat">[yyyy].['QTR'q].[MMM]</Annotation></Annotations> </Level>
Other Relative Date Filters
Other types of relative date filters are often used, especially the fiscal year in the business sector. A fiscal year will vary with each business and is based on how that business calculates its annual financial statements. You can define a Fiscal Calendar dimension in your Mondrian schema to accommodate this, and Analyzer will then use the current date to look up fiscal time periods in the fiscal time dimension.
For example, suppose a business has defined their fiscal year to always start on the first of May. Their fiscal time dimension table would look like this:
|Date||Fiscal Week||Fiscal Month||Fiscal Quarter||Fiscal Year|
Looking at the table and using a date such as 2014-05-01, we can find which Fiscal Week, Month, Quarter, or Year that it belongs to. Just look for the date in the table, then look further up the hierarchy to find 2015-M1. If you need to get the Current Month and Previous Month, you can first find 2015-M1 and then look back on the hierarchy to find 2014-M12, which is a sibling of 2015-M1 in the hierarchy.
There are a few key points to keep in mind about this dimension, before you get started.
- The bottommost level must be a Date, which will be used to look up a parent-level member based on the current date.
- The Date level must specify a new AnalyzerFiscalDateFormat annotation. This annotation value should specifiy a Java format string, which when evaluated with the current date, yields the MDX name of the Date level member. This format string should not include the format string for any parents above the Date level. This is different from the AnalyzerDateFormat annotation in which parents are also included in the format string.
- The Date level members must be unique within the level, so uniquemembers is set to true. This doesn't need to be the same for parent levels, but it is a good practice to do so since this is a time dimension.
- All levels in this hierarchy need to specify the levelType attribute.
- Levels above the Date level should not specify the AnalyzerDateFormat annotations.
Here is an example of a Fiscal Calendar dimension defined within a Mondrian schema:
<Dimension name="Fiscal Calendar" type="TimeDimension"> <Hierarchy hasAll="true" primaryKey="DATE_KEY"> <Table schema="FOODMART" name="CALENDAR"/> <Level name="Fiscal Year" levelType="TimeYears" column="FSC_YEAR_STR" uniqueMembers="true" type="String" ordinalColumn="FSC_YEAR" /> <Level name="Fiscal Quarter" levelType="TimeQuarters" column="FSC_QUARTER_YEAR_STR" uniqueMembers="true" type="String" ordinalColumn="FSC_DIM_QUARTER_NUM" /> <Level name="Fiscal Month" levelType="TimeMonths" column="FSC_MONTH_YEAR_STR" uniqueMembers="true" type="String" ordinalColumn="FSC_DIM_MONTH_NUM" /> <Level name="Fiscal Week" levelType="TimeWeeks" column="FSC_WEEK_YEAR_STR" uniqueMembers="false" type="String" ordinalColumn="FSC_DIM_WEEK_NUM" /> <Level name="Date" levelType="TimeDays" column="CAL_DATE" uniqueMembers="true" type="Date" ordinalColumn="DATE_KEY" > <Annotations><Annotation name="AnalyzerFiscalDateFormat">[yyyy-MM-dd]</Annotation></Annotations> </Level> </Hierarchy> </Dimension>
With this set up, Analyzer will be able to generate the MDX to turn a filter like Current Month into the correct Fiscal Month member:
Ancestor([Fiscal Calendar].[Date].[1997-06-28],[Fiscal Calendar].[Fiscal Month])
This MDX references a specific date member in the Date level, and then uses the Ancestor function to locate the parent month. Finding the Previous Month would be as simple as using the Lag MDX function:
Ancestor([Fiscal Calendar].[Date].[1997-06-28],[Fiscal Calendar].[Fiscal Month]).Lag(1)
Once you have these set up, your users will be able to apply this filter by selecting Choose a commonly used time period in the Filter on Fiscal Month dialog box.