element_at_map.sql

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--   http://www.apache.org/licenses/LICENSE-2.0
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statement
CREATE TABLE test_element_at_map(m map<string, int>, mi map<int, string>) USING parquet

statement
INSERT INTO test_element_at_map VALUES
  (map('a', 1, 'b', 2, 'c', 3), map(1, 'x', 2, 'y')),
  (map('x', 10), map(99, 'z')),
  (NULL, NULL)

-- key found
query
SELECT element_at(m, 'a'), element_at(m, 'b') FROM test_element_at_map

-- key not found → NULL
query
SELECT element_at(m, 'missing') FROM test_element_at_map

-- null map → NULL
query
SELECT element_at(CAST(NULL AS MAP<STRING, INT>), 'a')

-- null key → NULL
query
SELECT element_at(m, CAST(NULL AS STRING)) FROM test_element_at_map

-- integer key type
query
SELECT element_at(mi, 1), element_at(mi, 2), element_at(mi, 99) FROM test_element_at_map

-- key type coercion
query
SELECT element_at(mi, CAST(1 AS BIGINT)), element_at(mi, CAST(2 AS SMALLINT)) FROM test_element_at_map

-- literal map arguments
query
SELECT element_at(map('a', 1, 'b', 2), 'a'), element_at(map('a', 1, 'b', 2), 'missing'), element_at(map('a', 1, 'b', 2), NULL)