UnionArmRun	crates/gravity/lowerv4/src/face/slot_run.rs	make_end	lifetime	D1235	a union arm's run carrying its table copy grows in place	merge join	A merge join whose inner side sorts or materializes a UNION ALL keeps that inner side in memory where PostgreSQL's sort or Materialize spills to disk, so the statement fails with an out-of-memory error when the server has no more memory to give it.
