long integers

[Erik Max Francis]

Michael Hall wrote:

> I'm using Python 1.5.2 and am having trouble with long integers when I
> pull data out of a MySQL database using MySQLdb. When I retrieve a
> numeric value from a field with an `int' data type, the value has an
> `L'
> stuck on the end.

There are two standard methods of converting to a string: str and repr. 
repr is for converting to a representational string (nominally how it
would have been parsed, or surrounded in < and > otherwise), and str is
for pretty formatting.  The print statement implicitly converts its
arguments via str, not repr.

> In one script, I worked around this by stripping the L off with:
> 
> var = numeric_id # ("2L")
> var = var[:-1]
> print var
> >> 2

In 1.5.2 you're stuck with this solution; unfortunately, both str and
repr including the L suffix.  This was considered a defect and was fixed
in 2.0; in 2.0 and greater, str does not include the L suffix but repr
stil does.

> var = result[0] # ("2L")
> var = 'var[:-1]'
> print var
> >> var[:-1]

Presumably you meant backquotes here, not forward quotes:  `...` is
requivalent to repr(...).  Forward quotes ('...') are for quoting
strings, so 'var[:-1]' is literally the string "var[:-1]" (not an
evaluation of the expression), but `var[:-1]` is equivalent to
repr(var[:-1]).

Note that some (many?) consider the backquotes unsightly; you're
probably better off using repr.

> Can this be fixed in
> MySQL by changing or modifying the data type, or should I upgrade to a
> later version of Python?

It's fixed in Python 2.0 and up; upgrading and using str will solve the
problem.

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