Date attributes are organized within a hierarchy in each date dimension. For details, see Date Attribute Reference.
Chronological vs Generic Data Hierarchies
Chronological date attributes — categorize data with respect to particular past or future chronologically ordered dates and time intervals. Chronological attributes include Date,Week/Year, Month/Year, Quarter/Year, and Year. These attributes might have values such as Q2/2012, 08/25/2008, or January 2015.
The chart below shows a metric sliced by a chronological date attribute: Month/Year.
Generic date attributes — contain categories that group together all data relating to the same recurring time intervals. Examples include all data relating to Mondays, all data relating to January of any year, or all data relating to Q4 of any year. Labeling options for generic attributes may allow you to present values as named or numerical categories (April or Apr or M1/Q2 or M4).
The chart below slices a metric across the generic Month attribute. This means that the metric value associated with January, for example, represents an aggregation of all data from every month of January on record.
You could also slice this same metric across the generic Week attribute to help you look for patterns at the week level across multiple years of data.
Likewise, you could slice the same metric across the generic Week of Quarter attribute to help you look for trends within each quarter. Note how many fewer sales rep activities took place in the first and final weeks of each quarter.
Date Attribute Hierarchy
The date attributes that belong to each dimension are extrapolated from a single date value with a day, month, and year value (for example, 09/07/2012). Attributes in the "date tree" are derived from the hierarchy that is outlined below.
In the diagram above, Week/Year is not part of the greater chronological date attribute hierarchy because weeks often span across the ends of months, quarters, and years.