if an array traverses a list and the array is updated every few seconds, is the whole list updated, or is it a partial update that differs from the last update?
if an array traverses a list and the array is updated every few seconds, is the whole list updated, or is it a partial update that differs from the last update?
assume that every array has a unique KEY,. The updated part is the difference.
if there is no key, to refresh the entire list.
debugger process you will find that the whole list has been walked through.
in fact, when the upright page is rendered, only the data changes render .
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