flink-python/pyflink/table/tests/test_correlate.py

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from pyflink.table import expressions as expr
from pyflink.testing.test_case_utils import PyFlinkStreamTableTestCase


class CorrelateTests(PyFlinkStreamTableTestCase):

    def test_join_lateral(self):
        t_env = self.t_env
        t_env.create_java_temporary_system_function("split",
                                                    "org.apache.flink.table.legacyutils.TableFunc1")
        source = t_env.from_elements([("1", "1#3#5#7"), ("2", "2#4#6#8")], ["id", "words"])

        result = source.join_lateral("split(words) as (word)")

        query_operation = result._j_table.getQueryOperation()
        self.assertEqual('INNER', query_operation.getJoinType().toString())
        self.assertTrue(query_operation.isCorrelated())
        self.assertEqual('true', query_operation.getCondition().toString())

    def test_join_lateral_with_join_predicate(self):
        t_env = self.t_env
        t_env.create_java_temporary_system_function("split",
                                                    "org.apache.flink.table.legacyutils.TableFunc1")
        source = t_env.from_elements([("1", "1#3#5#7"), ("2", "2#4#6#8")], ["id", "words"])

        result = source.join_lateral(expr.call('split', source.words).alias('word'),
                                     expr.col('id') == expr.col('word'))

        query_operation = result._j_table.getQueryOperation()
        self.assertEqual('INNER', query_operation.getJoinType().toString())
        self.assertTrue(query_operation.isCorrelated())
        self.assertEqual('equals(id, word)',
                         query_operation.getCondition().toString())

    def test_left_outer_join_lateral(self):
        t_env = self.t_env
        t_env.create_java_temporary_system_function("split",
                                                    "org.apache.flink.table.legacyutils.TableFunc1")
        source = t_env.from_elements([("1", "1#3#5#7"), ("2", "2#4#6#8")], ["id", "words"])

        result = source.left_outer_join_lateral(expr.call('split', source.words).alias('word'))

        query_operation = result._j_table.getQueryOperation()
        self.assertEqual('LEFT_OUTER', query_operation.getJoinType().toString())
        self.assertTrue(query_operation.isCorrelated())
        self.assertEqual('true', query_operation.getCondition().toString())

    def test_left_outer_join_lateral_with_join_predicate(self):
        t_env = self.t_env
        t_env.create_java_temporary_system_function("split",
                                                    "org.apache.flink.table.legacyutils.TableFunc1")
        source = t_env.from_elements([("1", "1#3#5#7"), ("2", "2#4#6#8")], ["id", "words"])

        # only support "true" as the join predicate currently
        result = source.left_outer_join_lateral(expr.call('split', source.words).alias('word'),
                                                expr.lit(True))

        query_operation = result._j_table.getQueryOperation()
        self.assertEqual('LEFT_OUTER', query_operation.getJoinType().toString())
        self.assertTrue(query_operation.isCorrelated())
        self.assertEqual('true', query_operation.getCondition().toString())