Let say for example I have an excel file with 25 sheets.
Every sheet has 1mln records
I want to read only one sheet row by row.
Eg read the row and pass it the function.
Some of the rows have no data
Some of the cells have no data
But I still want to read all of them.
If I do not use virtual mode entire excel file will be loaded into memory plus it will load the sheets I don't need.
If I use virtual mode empty cells/rows will be skipped.
Yes, I can use a sparse array but again the entire sheet will be loaded into memory.
What would be the best approach from a performance/resources point of view?