determining the bounds of a tuple returned from a database

Fredrik Lundh fredrik at pythonware.com
Fri Nov 17 03:33:37 EST 2006


ronrsr wrote:

> very sorry, that was my error - len(result[0]) and len(result[1]) both
> return 1 --
> 
> i think I'm misunderstanding what len() does - to me they appear to
> have 2 or 3 elements, or at least be composed of a string of some
> length.

from python's perspective, the data structure you're looking at looks
like

    tuple of
        tuple of
             one string
        tuple of
             one string
        tuple of
             one string
    etc

so len(result) is the number of tuples, and len(result[index]) is the 
number of strings in the inner tuples (=1).  to get at an individual 
string, do

    s = result[index][0]

to look inside the string, you need to apply the appropriate string 
operations to extract the data, or split it up in some suitable way. 
there's no way Python can figure out how a string appears to you; from 
Python's perspective, it's just a bunch of characters.

</F>




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