MDEV-31279 Crash when lateral derived is guaranteed to return no rows
Consider this query SELECT t1.* FROM t1, (SELECT t2.b FROM t2 WHERE NOT EXISTS (SELECT 1 FROM t3) GROUP BY b) sq where sq.b = t1.a; If SELECT 1 FROM t3 is expensive, for example t3 has > thd->variables.expensive_subquery_limit, first evaluation is deferred to mysql_derived_fill(). There it is noted that, in the above case NOT EXISTS (SELECT 1 FROM t3) is constant and false. This causes the join variable zero_result_cause to be set to "Impossible WHERE noticed after reading const tables" and the handler for this join is never "opened" via handler::ha_open. When mysql_derived_fill() is called for the next group of results, this unopened handler is not taken into account. reviewed by Igor Babaev (igor@mariadb.com)
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