# UnionBehavior

Namespace: Deedle

This enumeration specifies the behavior of Union operation on series when there are overlapping keys in two series that are being unioned. The options include preferring values from the left/right series or throwing an exception when both values are available.

### Record Fields

 Record Field Description  Exclusive  Signature: UnionBehavior Modifiers: static When there are values available in both series that are being unioned, raise an exception.  PreferLeft  Signature: UnionBehavior Modifiers: static When there are values available in both series that are being unioned, prefer the left value.  PreferRight  Signature: UnionBehavior Modifiers: static When there are values available in both series that are being unioned, prefer the right value.