flatten()

Flatten a nested list by one level

Arguments & returns

Scalar

Overload link	`nested_list`	Returns
#01	`ANY[][]`	`ANY[]`

SELECT flatten([[1, 2, 3], [4, 5]]);

Haybarn WASM 1.5.5-rc3 · In your browser

Engine example · Run to view results.

SELECT ARRAY_CONCAT_AGG(arr) FROM (SELECT [1, 2] AS arr) AS t

In DuckDB

SELECT FLATTEN(ARRAY_AGG(arr) FILTER(WHERE NOT arr IS NULL)) FROM (SELECT [1, 2] AS arr) AS t

SELECT ARRAY_FLATTEN([[]])

In DuckDB

SELECT FLATTEN([[]])