Parsed test spec with 2 sessions

starting permutation: s1b s1d s2b s2i s1c s2c
step s1b: begin;
step s1d: delete from ppk where a = 1;
step s2b: begin;
step s2i: insert into pfk values (1); <waiting ...>
step s1c: commit;
step s2i: <... completed>
error in steps s1c s2i: ERROR:  insert or update on table "pfk1" violates foreign key constraint "pfk_a_fkey"
step s2c: commit;

starting permutation: s1b s1d s2bs s2i s1c s2c
step s1b: begin;
step s1d: delete from ppk where a = 1;
step s2bs: begin isolation level serializable; select 1;
?column?       

1              
step s2i: insert into pfk values (1); <waiting ...>
step s1c: commit;
step s2i: <... completed>
error in steps s1c s2i: ERROR:  could not serialize access due to concurrent update
step s2c: commit;

starting permutation: s1b s2b s1d s2i s1c s2c
step s1b: begin;
step s2b: begin;
step s1d: delete from ppk where a = 1;
step s2i: insert into pfk values (1); <waiting ...>
step s1c: commit;
step s2i: <... completed>
error in steps s1c s2i: ERROR:  insert or update on table "pfk1" violates foreign key constraint "pfk_a_fkey"
step s2c: commit;

starting permutation: s1b s2bs s1d s2i s1c s2c
step s1b: begin;
step s2bs: begin isolation level serializable; select 1;
?column?       

1              
step s1d: delete from ppk where a = 1;
step s2i: insert into pfk values (1); <waiting ...>
step s1c: commit;
step s2i: <... completed>
error in steps s1c s2i: ERROR:  could not serialize access due to concurrent update
step s2c: commit;

starting permutation: s1b s2b s2i s1d s2c s1c
step s1b: begin;
step s2b: begin;
step s2i: insert into pfk values (1);
step s1d: delete from ppk where a = 1; <waiting ...>
step s2c: commit;
step s1d: <... completed>
error in steps s2c s1d: ERROR:  update or delete on table "ppk1" violates foreign key constraint "pfk_a_fkey1" on table "pfk"
step s1c: commit;

starting permutation: s1b s2bs s2i s1d s2c s1c
step s1b: begin;
step s2bs: begin isolation level serializable; select 1;
?column?       

1              
step s2i: insert into pfk values (1);
step s1d: delete from ppk where a = 1; <waiting ...>
step s2c: commit;
step s1d: <... completed>
error in steps s2c s1d: ERROR:  update or delete on table "ppk1" violates foreign key constraint "pfk_a_fkey1" on table "pfk"
step s1c: commit;