v.23.11New Feature

Added arrayRandomSample SQL Function for Simplified Element Sampling

Official CH changelog text
Added a new SQL function, arrayRandomSample(arr, k) which returns a sample of k elements from the input array. Similar functionality could previously be achieved only with less convenient syntax, e.g. SELECT arrayReduce('groupArraySample(3)', range(10)). #56416 (Robert Schulze).
Introduced the SQL function arrayRandomSample(arr, k) which returns a random sample of k elements from the input array.

Why it matters

This feature simplifies extracting a random subset of elements from an array, replacing the previously more complex and less convenient syntax using arrayReduce('groupArraySample(k)', ...). It improves usability and readability for users needing to sample array data.

How to use it

Use the function by calling arrayRandomSample(arr, k), where arr is the input array and k is the number of random elements to sample. For example:

SELECT arrayRandomSample([1, 2, 3, 4, 5], 3)


returns three random elements from the given array.

Related resources

PreviousNext