sumMapWithOverflow

Introduced in: v20.1.0 Totals a value array according to the keys specified in the key array. Returns a tuple of two arrays: keys in sorted order, and values summed for the corresponding keys. It differs from the sumMap function in that it does summation with overflow - i.e. returns the same data type for the summation as the argument data type.

Passing a tuple of key and value arrays is identical to passing an array of keys and an array of values.
The number of elements in key and value must be the same for each row that is totaled.

Syntax

sumMapWithOverflow(key, value)
sumMapWithOverflow(Tuple(key, value))

Arguments

key — Array of keys. Array
value — Array of values. Array

Returned value Returns a tuple of two arrays: keys in sorted order, and values summed for the corresponding keys. Tuple(Array, Array) Examples Array syntax demonstrating overflow behavior

Query

CREATE TABLE sum_map(
    date Date,
    timeslot DateTime,
    statusMap Nested(
        status UInt8,
        requests UInt8
    ),
    statusMapTuple Tuple(Array(Int8), Array(Int8))
) ENGINE = Memory;

INSERT INTO sum_map VALUES
    ('2000-01-01', '2000-01-01 00:00:00', [1, 2, 3], [10, 10, 10], ([1, 2, 3], [10, 10, 10])),
    ('2000-01-01', '2000-01-01 00:00:00', [3, 4, 5], [10, 10, 10], ([3, 4, 5], [10, 10, 10])),
    ('2000-01-01', '2000-01-01 00:01:00', [4, 5, 6], [10, 10, 10], ([4, 5, 6], [10, 10, 10])),
    ('2000-01-01', '2000-01-01 00:01:00', [6, 7, 8], [10, 10, 10], ([6, 7, 8], [10, 10, 10]));

SELECT
    timeslot,
    toTypeName(sumMap(statusMap.status, statusMap.requests)),
    toTypeName(sumMapWithOverflow(statusMap.status, statusMap.requests))
FROM sum_map
GROUP BY timeslot;

Response

┌────────────timeslot─┬─toTypeName(sumMap⋯usMap.requests))─┬─toTypeName(sumMa⋯usMap.requests))─┐
│ 2000-01-01 00:01:00 │ Tuple(Array(UInt8), Array(UInt64)) │ Tuple(Array(UInt8), Array(UInt8)) │
│ 2000-01-01 00:00:00 │ Tuple(Array(UInt8), Array(UInt64)) │ Tuple(Array(UInt8), Array(UInt8)) │
└─────────────────────┴────────────────────────────────────┴───────────────────────────────────┘

Tuple syntax with same result

Query

SELECT
    timeslot,
    toTypeName(sumMap(statusMapTuple)),
    toTypeName(sumMapWithOverflow(statusMapTuple))
FROM sum_map
GROUP BY timeslot;

Response

┌────────────timeslot─┬─toTypeName(sumMap(statusMapTuple))─┬─toTypeName(sumM⋯tatusMapTuple))─┐
│ 2000-01-01 00:01:00 │ Tuple(Array(Int8), Array(Int64))   │ Tuple(Array(Int8), Array(Int8)) │
│ 2000-01-01 00:00:00 │ Tuple(Array(Int8), Array(Int64))   │ Tuple(Array(Int8), Array(Int8)) │
└─────────────────────┴────────────────────────────────────┴─────────────────────────────────┘

See Also

sumMap

​sumMapWithOverflow

sumMapWithOverflow