SQL Server 2019

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select datediff(month,'2020-12-01','2021-02-01')


(No column name)


2


create procedure devolverDIFF_Fechas 
  @Fcha1 datetime,
  @Fcha2 datetime
as
begin 

  declare @repeticiones int = datediff(month,@Fcha1,@Fcha2)
  declare @contador int = 0 
  declare @tabla_final table (fecha varchar(max))
  declare @ultimo_mes_fcha1 int = month(@Fcha1)
  declare @anio_a_colocar int = year(@Fcha1)

  insert into @tabla_final
        values(cast(@anio_a_colocar as varchar)+'-'+cast(@ultimo_mes_fcha1 as varchar)+
        '-'+cast(day(@Fcha1) as varchar))
  
  while @contador < @repeticiones begin 
        if @ultimo_mes_fcha1 = 12 begin 
             set @ultimo_mes_fcha1 = 1 
             set @anio_a_colocar += 1
        end 
        else begin 
          set @ultimo_mes_fcha1 += 1
        end 

        insert into @tabla_final
        values(cast(@anio_a_colocar as varchar)+'-'+cast(@ultimo_mes_fcha1 as varchar)+
        '-'+cast(day(@Fcha1) as varchar))

        set @contador+=1
  end 

  select *  
  from @tabla_final
end 
exec devolverDIFF_Fechas '2020-09-05', '2021-02-05'


fecha


2020-9-5

2020-10-5

2020-11-5

2020-12-5

2021-1-5

2021-2-5