20220803.1 performance comments, first questions (General)
In MariaDB (and my untested understanding for MySQL), using the STRAIGHT_JOIN in the SELECT will simply force the order of the JOINs as specified in the FROM clause, but will not force INNER JOIN for tables in the FROM clause. I have confirmed this to be true in MariaDB, and the LEFT JOINs still work properly.
The use of
STRAIGHT_JOIN is not without controversy. I didn't find a real recommendation but several critical posts.
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