sql joins as venn diagram
问题 I\'ve had trouble understanding joins in sql and came upon this image which I think might help me. The problem is that I don\'t fully understand it. For example, the join in the top right corner of the image, which colors the full B circle red and but only the overlap from A. The image makes it seem like circle B is the primary focus of the sql statement, but the sql statement itself, by starting with A (select from A, join B), conveys the opposite impression to me, namely that A would be the