Re: Inconsistent ::bit(N) and get_bit()?

2010/8/11 Boszormenyi Zoltan <zb@cybertec.at>:
> Shouldn't it at least be documented in more depth? Say, get_bit(, N)
> provides the Nth bit (0-based) counting from the leftmost bit?
> I would certainly appreciate a warning spelled out about this
> so if you convert a number to bitstring of length N and you want the
> Mth bit (according to any programming language) then you need to use
> get_bit(..., N-1-M).

The fact that bit-strings subscript from the left rather than from the
right seems pretty odd to me, but it is documented.  I wouldn't object
to adding a note to somewhere around here, if we can think of a
suitable way to word it:

http://www.postgresql.org/docs/9.0/static/functions-bitstring.html

-- 
Robert Haas
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