flatten function

Applies to: Databricks SQL Databricks Runtime

Transforms an array of arrays into a single array.

Syntax

flatten(expr)

Arguments

• expr: An ARRAY of ARRAY expression.

Returns

The result matches the type of the nested arrays within expr.

Azure Databricks raises COLLECTION_SIZE_LIMIT_EXCEEDED if the result exceeds the array size limit.

Common error conditions

• COLLECTION_SIZE_LIMIT_EXCEEDED

Examples

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

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