Marketing Cloud Automation Studio - Select the same column multiple times using aliases

Question

I'm trying to create a SQL query in Marketing Cloud Automation Studio, where I use the same column EventName from multiple tables _Sent, _Open, etc but I get an error message "The column 'EventDate' was specified multiple times for 'Qry'.

In my query I use multiple Inner Joins, and I used aliases to select the multiple EventDate columns from the different tables (S.EventDate, O.EventDate, B.EventDate, etc)

It seems that it's not possible to select multiple times columns with the same name, even when using aliases.

Answer 1

Based on the error message, it seems that you need to specify a different “output” name (alias) for each of those columns if you need all of them in the results, like this:

S.EventDate as SentEventDate,
O.EventDate as OpenEventDate, 
B.EventDate as BounceEventDate

Or, just include one of them in the query and disregard the rest as they are all the same anyway:

S.EventDate,
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