Locally-managed tablespaces can have one of two type of extent allocation, system-managed or uniform. System-managed extents are the default for permanent, locally-managed tablespaces and uniform extents are the default for temporary tablespaces.
		You can define a tablespace to have system-managed space allocation by using the keyword AUTOALLOCATE or by omitting the UNIFORM clause. When creating segments in such a tablespace, only the INITIAL value from the STORAGE clause is used, the server automatically sizes all other extents. The initial extent for any segment must be at least 64KB.
		If the UNIFORM keyword is specified, the tablespace is managed with uniform size extents. The default extent size is 1MB, but you can override this with a SIZE clause as shown in the example. In tablespaces with uniform extents, every extent will have the defined size regardless of any values listed in a segment's STORAGE clause.