sumCount

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.

Syntax

sumCount(x)

Arguments

• x — Input value, must be Integer, Float, or Decimal.

Returned value

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

Type: Tuple.

Example

Query:

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;

Result:

┌─sumCount(x)─┐
│ (190,20)    │
└─────────────┘

See also

• optimize_syntax_fuse_functions setting.