如果VLOOKUP错误返回，如何保留以前的Excel单元格值

Question

Reference Sheet: https://docs.google.com/spreadsheets/d/1UQVeVLLuZbre_RL0H68K1yQ_3ybY3mRIBYPJUfmf1k0/edit?usp=sharing

In above reference sheet, under row, if I change the "alpha", into "beta" the corresponding value will return error #N/A since the formula is not able to find the name reference. But I am trying to keep the previous value, instead of showing #N/A.

Eg: currently formula looking for alpha and corresponding value is 10, so the VLOOKUP fill value field with 10. If I change alpha into beta in "Row", the previous populated value corresponding to alpha, ie 10, will change to #N/A since vlookup not able to find the name which is looking for. but I need to keep the previous value 10 there instead #N/A eventhough vlookup not able to find that.

Answer 1

A formula will always evaluate the current values of precedents and there is no way to conditionally revert to the previous values of these precedents.

What you describe can be achieved with macros, where the VBA can be used to store previous values in backup scenarios. Such a scenario might be doable for a few cells but is impractical for a large data set.

You may want to re-think your data architecture. There may be other approaches than the one you are asking for.

Answer 2

Actually, I was able to do this using a formula.

=IFNA(VLOOKUP(value, table, col_index, [range_lookup]),current_cell)

current_cell will be the cell you are placing your formula on. The caveat in using this is that you will be creating a circular reference which might cause some of your calculations not work properly. But enabling iterations can be a work around for this.