Difference in the Drill-down behavior of Date Part and Date Value components of Date fields in Tableau

Typical conversion regarding the Drill-down behavior of Date fields in Tableau

What are Date Parts and Date Values in Tableau?

In Tableau when dealing with Dates we need to consider two terminologies
Whether it is a Date Part or Date Value?
Whether it is Discrete or Continuous?

For each date field (when we right-click it in Rows/Columns shelf) the top section of date components are always the Date Parts and the bottom section of dates are always the Date Values.

Location of Date Parts and Date Values in the Context Menu of a Date Field

The top group of dates (shown inside blue box) is the Date Part (Discrete), and this can be confirmed by the example data provided next to each option e.g.: May for Month.

The bottom group of dates (shown inside green box) is the Date Value (Continuous), and this can be confirmed by the example data provided next to each option e.g.: May 2015 for Month.

WARNING: DO NOT USE the Discrete and Continuous options (shown inside red box) at the bottom of this menu to switch back and forth between a discrete date and a continuous date.
It does not provide the same functionality and will work differently.

What are the possible combinations when working with Dates?

The Discrete or Continuous option always determines the color of the pill.
Discrete means Blue Pill and Continuous means Green Pill irrespective of if it is a Date Part or Date Value.
Discrete fields always create Headers and Continuous fields always create Axis/ Axes.

Hence in total we can have 4 possible combinations

Combination 1: Date Part (Discrete) — Blue Pill (More common combination for Discrete)

Date Part (Discrete) with Year date part selected (Blue pill)

Combination 2: Date Value (Continuous) — Green Pill (More common combination for Continuous)

Date Value (Continuous) with Year date value selected (Green pill)

Combination 3: Date Part (Continuous) — Green Pill (Less common combination for Continuous)

Date Part (Continuous) with Year date part selected (Green pill)

Combination 4: Date Value (Discrete) — Blue Pill (Less common combination for Discrete)

Date Value (Discrete) with Year date value selected (Blue pill)

Difference in the Drill-down behavior of Date Parts and Date Values?

When we click on + icon on the right-side of a Date Part pill/field the date hierarchy will expand to the right side retaining the existing date part.

Drill-down behavior of a Date Part field e.g: YEAR(Order Date)

We can drill down up to the DAY date part (or up how many levels of detail that the date field has in the data source).
Hence when we expand a Discrete Date Part we will get multiple pills.

Drill-down behavior of a Date Part field up to the DAY date part

If required we can rearrange the date parts based on the end user requirement. Hence the chronological order of dates need not be maintained. The order of data parts can be changed to get a different insight from the data.

Rearrangement of Date Parts is possible

But when we click on + icon on the right-side of a Date Value field the existing field will get transformed to the next field in the date hierarchy
i.e. : YEAR → QUARTER → MONTH → WEEK NUMBER → DAY etc.

Date Value Drill-down behavior as it gets transformed to the next field in the date hierarchy

Drill-down behavior of a Date Value field up to the DAY date part

When we consider Continuous Date Values the date chronology i.e. a level of detail in a timeline will be retained .

I hope this article is useful for all Tableau users especially for anyone just starting their Tableau journey!!!