Wesley Dodd/Dodds (first appearance = Adventure Comics #40, July 1939)
Garrett Sanford (first appeared in The Sandman #1, Winter 1974)
Hector Hall (revealed to have taken over Sanford's Sandman role in Infinty Inc. #50, May 1988)
Dream / Morpheus (The Sandman #1, January 1989 - DC then Vertigo)
Daniel Hall (son of Hector Hall; took over for Dream / Morpheus in Sandman #69, July 1995)
(Sanderson) "Sandy" Hawkins (originally Golden Age sidekick Sandy / later "Sand" then "Sandman")
Col. Larry Wilton (2002 one-shot Just Imagine Stan Lee With Walter Simonson Creating Sandman)
Kieran Marshall (2007 Sandman Mystery Theatre: Sleep of Reason mini-series)
other DC character? (please explain in separate post)