Entry dimensions are visit-based. They record the first dimension item, and persist it for the entire duration of that visit. Entry dimensions are available for all variables with pathing enabled under Traffic variables in Report suite settings.
A given entry dimension is based on its associated traffic variable. If the non-entry variable has data, its associated entry dimension also contains data. No implementation changes are required for entry dimensions if your traffic variables contain data.
Since entry variables are typically based on custom strings in your implementation, your organization determines what the dimension items are. Values in a given entry dimension match dimension items in its associated non-entry dimension. For example, dimension items in the ‘Entry page’ dimension contain similar dimension items in the ‘Page’ dimension.
The ‘Entry page original’ dimension operates differently than other entry dimensions. Instead of preserving the entry page for a given visit, it preserves the very first entry page for the entire life of that visitor’s cookie. For example, if you land on
https://example.com/page4 for your first visit to the site, then a year later land on
https://example.com/store, The ‘Entry page original’ dimension lists
https://example.com/page4 as the dimension item.