> If you really need to match all those options, you can't use an index. A
> substring-matching index would need to have multiple entries per
> character per value (since it doesn't know what you will search for).
> The index-size becomes unmanageable very quickly.
> That's why I asked what you really wanted to match.
To be more specific, in fact, our current application allows to delete
email(s) with a minimum of 3 characters. There is a note/warning also given
for application Users' before deleting, explaining the implication of this
delete action (partial & case-insensitive, and it could be wide-ranging
too).
> So, I'll ask again: do you really want to match all of those options?
Yes, as explained above, I want to match all those.