You are absolutely right! Just a side note, if you use SQL between operator, you have to be aware that the values specified after the BETWEEN operator are inclusive. So if you say:

select first_name, last_name, credit_limit
from customer
where credit_limit between 500 and 800
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The result set will include those ones with credit limit equal to 500 or 800. If you want to exclude those people, you have to write a query like this:

select first_name, last_name, credit_limit
from customer
where credit_limit > 500 and credit_limit < 800
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