MAP_FROM_ARRAYS

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Syntax

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Scalar

map_from_arrays(keys, values)

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Arguments

• K is the map key type: BOOLEAN, TINYINT, SMALLINT, INTEGER, BIGINT, FLOAT, DOUBLE, DECIMAL(p, s), STRING, BINARY, DATE, TIME, TIMESTAMP, ARRAY or STRUCT.
• V is the map value type: BOOLEAN, TINYINT, SMALLINT, INTEGER, BIGINT, FLOAT, DOUBLE, DECIMAL(p, s), STRING, BINARY, DATE, TIME, TIMESTAMP, ARRAY, MAP or STRUCT.

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Returns

• Type: MAP<K,V>
• Possible values: The paired map entries.
• NULL behavior: Returns NULL if either array is NULL. NULL map keys raise an error; NULL values are allowed.
• Shape: One entry per distinct key.
• Ordering: Map entries are not sorted. Their order follows insertion and duplicate removal.

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Properties

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Usage notes

• Duplicate keys raise an error for Databricks source dialect; other dialects use the last value for a repeated key.
• NaN and signed zero keys are normalized for duplicate comparisons.
• For last-wins duplicate handling, the retained entries appear in the original order of the surviving last occurrences, without key sorting.
• INTEGER and INT mean the same type; STRING means VARCHAR text. NULL can be used with a supported type. Cast NULL explicitly when its type would otherwise be unclear.

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Examples

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Typical behavior

SELECT map_from_arrays(ARRAY['a', 'b'], ARRAY[1, 2]) AS "value";

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Duplicate keys, Databricks dialect

• Databricks dialect; duplicate-key errors enabled.

SELECT map_from_arrays(ARRAY[CAST(1 AS INT), CAST(1 AS INT)], ARRAY['a', 'b']) AS result;

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Limitations

• Arrays of different lengths or arrays containing NULL keys raise an execution error.