2486226 - Why does the function returns the same result when the 'Null' value is used? - SAP ASE

When the 'Null' value or constant value is used as a input parameter, the return value of function is the same regardless of the number of returned rows.

select a, dbo.sp_f_nextval('user_action_seq', NULL) from zzz
go
 a
 -------------------- ---------------------------------
 abc                                                 1
 def                                                  1

select a, dbo.sp_f_nextval('user_action_seq', a) from zzz
go
 a
 -------------------- ---------------------------------
 abc                                                 2
 def                                                  3

SAP Adaptive Server Enterprise (ASE)

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