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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