How to Create a Dynamic Grid with Month-Year Columns Based on Date Range selection in Appian?

If you plan to use a normal read only grid, you can create any number of columns dynamically. 

My approach to such tasks is, to first build a small prototype, assuring myself that I understand the challenge and I have solutions to all the tiny problems making up the whole thing.

E.g. to get the dynamic list of months, you can use code like this:

a!localVariables(
  local!start: today(),
  local!end: date(2026, 11, 15),
  local!numMonths: (12 * year(local!end) + month(local!end)) - (12 * year(local!start) + month(local!start)),
  local!months: a!forEach(
    items: enumerate(local!numMonths),
    expression: a!addDateTime(
      startDateTime: local!start,
      months: fv!item
    )
  ),
  local!months
)

Hi Stefan Helzle Thanks for the support so far!

I’ve made good progress — I’m able to:

 Generate all dates between the selected date range

 Display dynamic Month-Year columns in a grid

 Populate each cell with the correct ForecastAmount for its respective ActivityName and Month-Year, using an expression rule

However, I’m facing a performance issue now.

Since the dataset contains millions of records, and each cell in the Month-Year columns is calling an expression rule to get its value, the performance has become very slow.

My Question:

Is there a better or more efficient way to display these Month-Year forecast values without making individual rule calls for each cell?

Would it be better to:

• Preprocess and pivot the data in a single rule before binding it to the grid?
• Use a different design approach or plug-in to optimize performance?

Any suggestions or best practices for handling large datasets with dynamic grids would be really helpful.

Hi Stefan Helzle Thanks for the support so far!

I’ve made good progress — I’m able to:

 Generate all dates between the selected date range

 Display dynamic Month-Year columns in a grid

 Populate each cell with the correct ForecastAmount for its respective ActivityName and Month-Year, using an expression rule

However, I’m facing a performance issue now.

Since the dataset contains millions of records, and each cell in the Month-Year columns is calling an expression rule to get its value, the performance has become very slow.

My Question:

Is there a better or more efficient way to display these Month-Year forecast values without making individual rule calls for each cell?

Would it be better to:

• Preprocess and pivot the data in a single rule before binding it to the grid?
• Use a different design approach or plug-in to optimize performance?

Any suggestions or best practices for handling large datasets with dynamic grids would be really helpful.