My laptop:
oao_trial=> explain analyze insert into test values (7418880);
QUERY PLAN
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Insert on test (cost=0.00..0.01 rows=1 width=0) (actual time=0.280..0.280 rows=0 loops=1)
-> Result (cost=0.00..0.01 rows=1 width=0) (actual time=0.002..0.004 rows=1 loops=1)