Array functions

array_sort()

Signature:

array_sort(array: ARRAY<T>) -> ARRAY<T>

Returns a array with the sorted order of the array. T must be an orderable type. Null elements are placed at the end of the returned array. May throw an error if T is a ARRAY or ROW type and input values contain nested nulls.

array_sort(array: ARRAY<T>, lambda: FUNCTION(T) -> U) -> ARRAY<T>

Returns the array sorted by values computed using the specified lambda in ascending order. U must be an orderable type. Null elements will be placed at the end of the returned array. May throw if T is an ARRAY or ROW type and input values contain nested nulls. Throws if deciding the order of elements would require comparing nested null values.

Example:

MATCH (n:Person) RETURN array_sort(n.friends);
MATCH (n:Person) RETURN array_sort(n.friends, x -> x.age) AS sorted_friends;

array_sort_desc()

Signature:

array_sort_desc(array: ARRAY<T>) -> ARRAY<T>

Returns the array sorted in descending order. T must be an orderable type. Null elements will be placed at the end of the returned array. May throw if T is an ARRAY or ROW type and input values contain nested nulls. Throws if deciding the order of elements would require comparing nested null values.

array_sort_desc(array: ARRAY<T>, lambda: FUNCTION(T) -> U) -> ARRAY<T>

Returns the array sorted by values computed using the specified lambda in descending order. U must be an orderable type. Null elements will be placed at the end of the returned array. May throw if T is an ARRAY or ROW type and input values contain nested nulls. Throws if deciding the order of elements would require comparing nested null values.

Example:

MATCH (n:Person) RETURN array_sort_desc(n.friends) AS sorted_friends;
MATCH (n:Person) RETURN array_sort_desc(n.friends, x -> x.age) AS sorted_friends;

transform()

Signature:

transform(array: ARRAY<T>, function: FUNCTION(T) -> U) -> ARRAY<U>

Returns an array that is the result of applying the function to each element of the input array.

Example:

RETURN transform(ARRAY[0, 1], x -> x + 0.1);

arrays_union()

Signature:

arrays_union(x: ARRAY<T>, y: ARRAY<T>) -> ARRAY<T>

Returns an array of the elements in the union of x and y, without duplicates. For FLOAT and DOUBLE, NANs (Not-a-Number) are considered equal.

Example:

RETURN arrays_union(ARRAY[1, 2, 3], ARRAY[3, 4, 5]);

size()

Signature:

size(array: ARRAY<T>) -> BIGINT

Returns the number of elements in the array.

Example:

RETURN size([1, 2, 3, 4])

range()

Signature:

range(start: BIGINT, end: BIGINT [, step: BIGINT]) -> ARRAY<BIGINT>

Returns a array comprising all integer values within a specified range.

Example:

RETURN range(0, 10)

reduce()

Signature:

reduce(accumulator = initial, variable IN array| expression) -> T

Applies an expression to each element in a array, carrying over the result of the computation to the next element.

Example:

RETURN reduce(total = 0, n IN [1, 2, 3, 4] | total + n)

reverse()

Signature:

reverse(array: ARRAY<T>) -> ARRAY<T>

Returns a array in which the order of all elements in the original array have been reversed.

Example:

RETURN reverse([1, 2, 3, 4])

tail()

Signature:

tail(array: ARRAY<T>) -> ARRAY<T>

Returns all elements of the array except the first one.

Example:

RETURN tail([1, 2, 3, 4])

to_boolean_array()

Signature:

to_boolean_array(array: ARRAY<T>) -> ARRAY<BOOLEAN>

Converts a array of values to a array of boolean values.

Example:

RETURN to_boolean_array(['true', 'false', 'true'])

to_double_array()

Signature:

to_double_array(array: ARRAY<T>) -> ARRAY<DOUBLE>

Converts a array of values to a array of double values.

Example:

RETURN to_double_array(['1.1', '2.2', '3.3'])

to_bigint_array()

Signature:

to_bigint_array(array: ARRAY<T>) -> ARRAY<BIGINT>

Converts a array of values to a array of bigint values.

Example:

RETURN to_bigint_array(['1', '2', '3'])

to_varchar_array()

Signature:

to_varchar_array(array: ARRAY<T>) -> ARRAY<VARCHAR>

Converts a array of values to a array of varchar values.

Example:

RETURN to_varchar_array([1, 2, 3])