Count functions
These functions can be used when counting field values and expressions.
Function | Description |
---|---|
count()
|
Counts a row, or whether a given value is truthy |
count
The count
function counts the number of times that the function is called. This is useful for returning the total number of rows in a SELECT
statement with a GROUP BY
clause.
count() -> 1
If a value is given as the first argument, then this function checks whether a given value is truthy. This is useful for returning the total number of rows, which match a certain condition, in a SELECT
statement, with a GROUP BY
clause.
count(any) -> number
If an array is given, this function counts the number of items in the array which are truthy. If, instead, you want to count the total number of items in the given array, then use the array::len()
function.
count(array) -> number
The following examples show this function, and its output, when used in a RETURN
statement:
RETURN count();
1
RETURN count(true);
1
RETURN count(10 > 15);
0
RETURN count([ 1, 2, 3, null, 0, false, (15 > 10), rand::uuid() ]);
5
The following examples show this function being used in a SELECT
statement with a GROUP
clause:
SELECT count() FROM [{ age: 33 }, { age: 45 }, { age: 39 }] GROUP ALL;
3
SELECT count(age > 35) FROM [{ age: 33 }, { age: 45 }, { age: 39 }] GROUP ALL;
2
An advanced example of the count function can be seen below:
SELECT
country,
count(age > 30) AS total
FROM [
{ age: 33, country: 'GBR' },
{ age: 45, country: 'GBR' },
{ age: 39, country: 'USA' },
{ age: 29, country: 'GBR' },
{ age: 43, country: 'USA' }
]
GROUP BY country;
[
{
country: 'GBR',
total: 2
},
{
country: 'USA',
total: 2
}
]