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SET client_min_messages=NOTICE;
CREATE EXTENSION multicorn;
CREATE server multicorn_srv foreign data wrapper multicorn options (
wrapper 'multicorn.testfdw.TestForeignDataWrapper'
);
CREATE user mapping for postgres server multicorn_srv options (usermapping 'test');
-- Test for two thing: first, that when a low total row count,
-- a full seq scan is used on a join.
CREATE foreign table testmulticorn (
test1 character varying,
test2 character varying
) server multicorn_srv options (
option1 'option1'
);
explain (costs off) select * from testmulticorn;
explain (costs off) select * from testmulticorn m1 inner join testmulticorn m2 on m1.test1 = m2.test1;
explain (costs off) select * from testmulticorn m1 left outer join testmulticorn m2 on m1.test1 = m2.test1;
DROP foreign table testmulticorn;
-- Second, when a total row count is high
-- a parameterized path is used on the test1 attribute.
CREATE foreign table testmulticorn (
test1 character varying,
test2 character varying
) server multicorn_srv options (
option1 'option1',
test_type 'planner'
);
explain (costs off) select * from testmulticorn;
explain (costs off) select * from testmulticorn m1 inner join testmulticorn m2 on m1.test1 = m2.test1;
explain (costs off) select * from testmulticorn m1 left outer join testmulticorn m2 on m1.test1 = m2.test1;
DROP EXTENSION multicorn cascade;
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