Can sodium chloride be categorised as a giant molecular structure

[mutineer123]

I was attempting this question where I had to say which, out of graphite, diamond and sodium chloride represent a giant molecular structure? The answer is only the first two. Why is the latter excluded?

 

[Borek]

What kind of bonds keeps atoms together in each crystal?

 

[mutineer123]

covalent in first,ionic in last

 

[aroc91]

Stemming from that, a molecule is defined as two or more atoms covalently bonded. By definition, ionic bonds are excluded.