Map(key, value)
Parameters
- key
— The key part of the pair. String or .
- value
— The value part of the pair. String, or Array.
Warning
Currently Map
data type is an experimental feature. To work with it you must set .
Examples
Consider the table:
Select all key2
values:
If there’s no such in the Map()
column, the query returns zeros for numerical values, empty strings or empty arrays.
INSERT INTO table_map VALUES ({'key3':100}), ({});
Result:
You can cast Tuple()
as using function:
SELECT CAST(([1, 2, 3], ['Ready', 'Steady', 'Go']), 'Map(UInt8, String)') AS map;
- CAST() function