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You can edit the way your information from Data blaze is displayed to achieve this. In this case your data is in a list. You can read about editing lists here. For your case, this should work:
{note}{dbselect: SELECT Email FROM `NOVOTEST Clients`; space=1AWQohMnJ84AhfP7gC3CyL; menu=no; multiple=yes}{endnote}
{=join(email, "BLAZE_AND")}
This will input your email, separated by a comma, with "and" at the last entry. You can replace the second parameter of "join" to any separator you wish.