问题
I have a line chart where the Y value is set to
=CountRows()
and I have a Category Group which groups on
=CDate(Fields!END_MONTH_NB.Value)
I am trying to set the interval of the Y axis dynamically such that fractions do not appear when the range is too small (see below).
I tried setting the interval expression to
=iif(CountRows() <= 5, 1, "Auto")
which works fine if the total number of rows is less than or equal to 5, but what I really need is the maximum that CountRows() will return in the context of my Category Group.
Any idea how to accomplish this?
回答1:
Since you're using SSRS 2012, you can use the aggregate of an aggregate functionality to achieve this.
Say I have a chart like this, similar to yours:
With the appropriate data, it has the same issue as your screenshot, even with an expression in the Y-Axis interval:
i.e. here there are 8 rows, so the expression will be set to Auto, but because the groups have no more than three rows we get fractions in the Y axis.
We can get around this by finding the maximum of each of these group counts.
The Category Group will have a name:
Here I've called it MonthGroup. With this, we can change the Y Axis interval expression:
=IIf(Max(CountRows("MonthGroup")) <= 5, 1, Nothing)
i.e. if <=5, interval is 1, otherwise just pass a NULL value, i.e. let SSRS determine the interval.
So now we're checking the Max of the Category Group level CountRows; this is 3 in my example so now we're getting the required axis intervals:
Edit note:
Previously I had the Y Axis expression as:
=IIf(Max(CountRows("MonthGroup")) <= 5, 1, "Auto")
But after posting I noticed this was causing a warning in some circumstances; presumably because Auto is not a valid interval; it's just a placeholder used by SSRS. The updated expression:
=IIf(Max(CountRows("MonthGroup")) <= 5, 1, Nothing)
Works as expected without warnings.
来源：https://stackoverflow.com/questions/18128069/ssrs-line-chart-dynamic-y-axis