Removing a table key?

[zork]

Assuming I want to save guids. At some point in the future I want to remove outdated guids.

local guids = {}
 
local guidA = "12345"
local guidB = "ABCDE"
 
guids[guidA] = { time=time(), hp=UnitHealth(guidA) }
guids[guidB] = { time=time(), hp=UnitHealth(guidB) }

*edit* Just found what I was looking for in the last sentence.

Note that table.remove only works with numeric indexes. For dictionaries you can just unset tables entries with tablevariable["index"] = nil; http://lua-users.org/wiki/TableLibraryTutorial

So I guess I will do this

for k,v in ipairs(guids) do 
  if time()-3600 > v.time then
    guids[k] = nil
  end
end

Question. If I set the table value for a key to nil. When ipairs is called again. Will ipairs return keys with a value of nil?