'Joining' two tables with column that has same data, but different name

I know JOINs are not supported, but have seen that you can simulate it with FACET if the two tables have the same column/attribute name.

SELECT
count(*)
FROM
A, B FACET sharedId, B.otherStuff
SINCE 1 MONTH AGO LIMIT MAX

Assuming A and B both have an attribute called sharedId.

However, what if the attribute names are different in the two tables, even though they are the same data. What is the syntax then?

i.e.
A.join_id and B.my_join_id are the same unique ID to ‘join’ the table, but their names are different (join_id versus my_join_id). I can’t use the syntax in the query above, unless there is a workaround using as or something?

Is it that you want to count the value as 1 even if the value is in both A and B event types in different attribute names?

Yes, count(1).

For a bit of background, our organisation created a custom event called ‘BrowserInteractionSpan’ that (literally) joined the BrowserInteraction and Span tables so we could more easily query the data for our particular purposes. In particular, we got the error.statusCode from Span and added it to BrowserInteraction so that we could associate http status codes with errors on particular pages, but also consider the previous page url (only available in BrowserInteraction).

I want to ‘join’ BrowserInteractionSpan.span.traceId to TransactionError.traceId, without using custom event, so I can report on extra things in TransactionError (B) associated with BrowserInteractionSpan (A). Unfortunately the attribute names are different (span.trace.id vs traceId). Perhaps, I’m barking up the wrong tree completely though.