# explain select a.id,b.id,a.note from testtab01 a, testtab02 b where a.id=b.id and b.id<=1000000;
QUERY PLAN
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Hash Join (cost=20000041250.75..20000676975.71 rows=999900 width=93)
Hash Cond: (a.id = b.id)
-> Seq Scan on testtab01 a (cost=10000000000.00..10000253847.55 rows=10000055 width=89)
-> Hash (cost=10000024846.00..10000024846.00 rows=999900 width=4)
     -> Seq Scan on testtab02 b (cost=10000000000.00..10000024846.00 rows=999900 width=4)
      Filter: (id <= 1000000

按照从上到下顺序的话

这个执行顺序感觉是先testtab01 ，然后 testtab02 吗？

还是先执行testtab02，再执行testtab01 吗？