Erm... "Either char(1) or varchar(1) may be used. Both would allocate 1 byte of space which would be used. [If there's no data in the variable, varchar would be a better option to use, since char would have allocated and 'used' (padding with space), the space allocated]. "
Regardless of points (what's a point here and there, right? :-P), I strongly disagree with statements like this being paraded as fact on such a high profile site / source of SQL info. I mean, out of the two even an empty char(1) takes up less space than an empty varchar(1), right?
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