sumCount

Introduced in: v21.6.0

Calculates the sum of the numbers and counts the number of rows at the same time. The function is used by ClickHouse query optimizer: if there are multiple sum, count or avg functions in a query, they can be replaced to single sumCount function to reuse the calculations. The function is rarely needed to use explicitly.

See also

optimize_syntax_fuse_functions setting.

Syntax

sumCount(x)

Arguments

x — Input value. (U)Int* or Float or Decimal

Returned value

Returns a tuple (sum, count), where sum is the sum of numbers and count is the number of rows with not-NULL values. Tuple

Examples

Basic usage

CREATE TABLE s_table (x Int8) ENGINE = Log;
INSERT INTO s_table SELECT number FROM numbers(0, 20);
INSERT INTO s_table VALUES (NULL);
SELECT sumCount(x) FROM s_table;

┌─sumCount(x)─┐
│ (190,21)    │
└─────────────┘

See also

optimize_syntax_fuse_functions setting.