what everyone else said, but:
I want to store settings (metadata) containing 600+ key value pairs.
>
>
key: value pairs are made for attributes.
> I could store them as attributes with a key and a 1D array of values,
> which has the advantage that I have all the metadata within the .nc file.
>
> In an extreme case the array will grow to a thousand entries.
>
>
If you have an array of thousands of entries that map to a single key --
you should put that in a variable, not attributes.
You might use attributes to map the key to the particular variable name.
Alternatively I would store the settings history in a separate text file.
>
definitely not!
-CHB
>
-- 
Christopher Barker, Ph.D.
Oceanographer
Emergency Response Division
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