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The FLATTEN-RECORD directive splits RowType (Record) column a record column with nested values into multiple columns. To flatten an array, use the FLATTEN directive.
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The column
is the name of a RowType record column with nested values.
Usage
The directive takes multiple columns of type "Row" as and brings all its elements up a level. Topmost elements will be set under new columns prefixed with the name of the parent column followed by an underscore. Existing columns with the same name will be replaced by the new values.
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