Presumably something like this?:

maciek=# CREATE TABLE test AS SELECT g, random() FROM
generate_series(1,1000) g;
CREATE
maciek=# EXPLAIN DELETE FROM test USING (SELECT g FROM test ORDER BY
ctid) x where x.g = test.g;
                                   QUERY PLAN
---------------------------------------------------------------------------------
 Delete on test  (cost=188.99..242.34 rows=1940 width=34)
   ->  Hash Join  (cost=188.99..242.34 rows=1940 width=34)
         Hash Cond: (x.g = public.test.g)
         ->  Subquery Scan on x  (cost=135.34..159.59 rows=1940 width=32)
               ->  Sort  (cost=135.34..140.19 rows=1940 width=10)
                     Sort Key: public.test.ctid
                     ->  Seq Scan on test  (cost=0.00..29.40 rows=1940 width=10)
         ->  Hash  (cost=29.40..29.40 rows=1940 width=10)
               ->  Seq Scan on test  (cost=0.00..29.40 rows=1940 width=10)
(9 rows)


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