Here is an answer I recently gave to a client for a similar situation.
I don't have that exact code handy in any apps, but the idea would be to set up a custom Key field for the target table in the format like A-1234 and B-1234, representing the records from tables A and B, and the Record ID#'s of each table. The prefix ensures that the custom Key would never duplicate across two tables. Make those as formula fields in each source table.
Create two saved table to table copy imports to populate the target table.
Then the code would be something like this, (not tested for syntax)
var text Purge = URLRoot() & "db/" & [_DBID_CONSOLIDATED_TABLE] & "?act=API_PurgeRecords";
var text ImportOne = URLRoot() & "db/" & [_DBID_CONSOLIDATED_TABLE] & ?act=API_RunImport&ID-=10";
var text ImportTwo = URLRoot() & "db/" & [_DBID_CONSOLIDATED_TABLE] & ?act=API_RunImport&ID-=11";
var text DisplayTableHomePage = URLRoot() & "db/" & [_DBID_CONSOLIDATED_TABLE] & "?a=td":
$Purge
& "&rdr=" & URLEncode($ImportOne)
& URLEncode("&rdr=" & URLEncode($ImportTwo))
& URLEncode(URLEncode("&rdr=" & URLEncode($DisplayTableHomePage)))
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Mark Shnier (Your Quickbase Coach)
mark.shnier@gmail.com
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