The script and the amount of data aren't really important here else the used expressions within this object which should be as simple as possible by avoiding nested if-loops and aggr- or interrecord-functions.
You need some method to limit the max. amount of records in the object. A tablebox or a table-chart is only usable until a few hundreds or maybe thousands of records but not many millions - which then hits the memory-threshold for this object. In qlikview you could just use calculation-conditions as an option within the object by sense I don't know if this is natively or per extension available. If not I think any workaround will be possible maybe with a condition in a dimension or expression by a table-chart.
Even if the object could display so much records the export of the data would be take a very long time - probably more as practically and I assume there would be other issues too.
Therefore I think you should create a specialized load for it which stored these data into txt-file and send it to the client or give him access to it.
Showing a table-box with millions of rows is pointless to a user, can't interact with it even if it shows. If you don't use all that data in other GUI objects it is of no use and it will considerably slow down the whole application.
Either do a load and store to file in script or do a export directly in the database.
You already have it as QVD, you could as easily store it as a CSV and give to your client.
