Performs a union operation on a set of geography objects.
|Applies to: SQL Server ( SQL Server 2012 through current version), Azure SQL Database.|
UnionAggregate ( geography_operand )
Is a geography type table column that holds the set of geography objects on which to perform a union operation.
SQL Server return type: geography
Method returns null if the input has different SRIDs. See Spatial Reference Identifiers (SRIDs).
Method ignores null inputs.
Method returns null if all inputted values are null.
The following example performs a
UnionAggregate on a set of geography location points within a city.
geography::UnionAggregate(SpatialLocation) AS SpatialLocation
WHERE PostalCode LIKE('981%')
GROUP BY City;