This looks straightforward if you import the CSV file as a report instead of as a database. Just changing the file extension to ".prn" should tell Monarch to treat it as a text report.
Then one detail template, using the floating trap, on the "Level" for the detail, and an Append template, on the 1 7084 characters. This will get the data you need into a table.
After that, a summary with the Level as an across key and a measure of Unique(Value) should give you what you need. Make sure the Value field (e.g. 99051) is defined as numeric.
This assumes that the value field is always numeric, that you don't need to preserve leading zeroes, and that you have one value only at each level for each code.
Thanks for reply.
I may not be in a position to use your suggestion as once I import the data into the report window, I'll be using many functions/rules/etc. Also, as I've mentioned earlier, I may not be in a position to convert this into a .txt or .prn file as I've to convert more than 500 columns, which will be difficult.
The summary window will not help me to do the calculations.
If you have a CSV file, you can rename it as a PRN file regardless of how many columns there are. If you have more than 254 columns you won't be able to import them into Monarch in one model.
There's nothing in the approach I proposed to stop you from adding filters and calculated fields to the data in the table window, to help you export exactly what you need from the summary window.