Answer 1

~ swim ~
Will it work if for example we create a temporary string object first (just to mix the e-mail and password in) then assign the temporary string buffer into a constant char pointer, maybe like this;

string email {"my_e-mail"}, pass {"my_password"};
string s {"INSERT INTO Accounts (EMAIL, PASSWORD) VALUES ('" + email + "', '" + pass + "');"};
const char* sql = s.c_str();
printf("%s\n", sql); // verify

But is this right by standard? I don't know ...

Answer 2

Yes I get it. So we can't use the <sql> variable outside function because the data it refers to is a local variable <s> string 👍