I guess it bears repeating that expecting GIS data structures to behave like spreadsheets - especially in terms of a 'totals' row - is usually going to result in disappointment. More so with the Attribute Table layout item which is just a derivative of source data - I don't think QGIS stores the location of each row.
You could use a convoluted expression - or Python, or generate a virtual layer maybe - to:
- generate unique aggregates based on map layout visibility
- sort the results in the specific order required and extract the 2nd and 4th rows from #1 - OR reference the specific rows by an identifying value (e.g.
"item type" = 'point')
- extract the required aggregate values from #2
- Sum the results from #3
...but you would still need the "totals" row to be a separate table or text box rather than within the attribute table.
I am not sure how you generated an attribute table that has both sums and counts as separate rows rather than columns.
But to prove that the concept is technically possible, here is an example where I have counted the heights of trees visible in an atlas feature grouped by genus, ordered by genus.
In a separate table I calculated the combined heights of relevant trees; the first column just had static text (e.g. 'Sum of blah') and the second text had an expression. I also filtered this table to show only 1 row, otherwise it would iterate the same value over every feature in the source layer.
For this example I created two such tables, (a) the 2nd and 4th rows (much more convoluted), and (b) the total number of trees that are genus Acacia or Eucalyptus.
But I don't think trying to sum 'the second and fourth rows' is ever a good approach - that's just not good data structuring, if you can instead reference particular values that would be more robust.
Here is the code for table (a)
with_variable('results',
array_distinct(
array_agg(sum("height_m",
group_by:="genus",
filter:=intersects($geometry,@atlas_geometry)),
filter:=intersects($geometry,@atlas_geometry),
order_by:="genus")),
@results[1]+@results[3])
And the code for table (b)
array_sum(
array_distinct(
array_agg(sum("height_m",
group_by:="genus",
filter:=intersects($geometry,@atlas_geometry)),
filter:=intersects($geometry,@atlas_geometry)
and "genus" in ('Acacia','Eucalyptus'))))
Replace "genus" with the attribute you want to group by,"height_m" for the attribute you want to aggregate, and 'Acacia' and 'Eucalyptus' with any specific values you want to reference for table (b)
Best Answer
Any map item (image, label, ...) can have a border - it just needs to be enabled. Then you arrange the items and that should be it. You can also insert HTML tables in label items:
Afaik, there is no functionality to group items in the print composer item panel. If it gets too cumbersome to reproduce the standardized "Plankopf", you might consider adding it as a picture and then just throwing labels/images on top