Hi again Sarah,
I see you're acclimating to Xcalar Design 1.3.1. I'm glad your team was able to find the window to upgrade!
Cross join, like right semi join, has a distinct purpose, as detailed in this article, it is an explosive query that creates a row for each combination of rows in the primary and secondary table.
The most common use would be cross joining a table of customers with a table of survey fields to prepare to send a survey to your customer base.
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