Attached script causes memory read error at sqlite3.pyd.
Tested on Python 2.5.1/Windows XP.

I can't reproduce this on Linux with valgrind.  Did you use purify to find this problem?

Can you provide the complete report that shows the memory read error with the call stack?  
Are you sure the problem is in the python code?  
Could the problem be in the sqlite code itself?

Purify is not needed to find this problem, since python aborts 
by running test script. VisualC++ reports memory read error occurred.

Problem might be in the sqlite, not sqlite3. I'm not sure which is. 
I failed to find this problem at sqlite's trac.

Here's stack trace::

sqlite3.dll!60931bb0() 	
_sqlite3.pyd!00ac5887() 	
_sqlite3.pyd!00ac589e() 	
_sqlite3.pyd!00ac3e6f() 	
_sqlite3.pyd!00ac4251() 	
python25.dll!PyCFunction_Call(_object * func=0x00bedd78, _object * arg=0x00be66f0, _object * kw=0x00000000)  行 73 + 0x8	C
python25.dll!call_function(_object * * * pp_stack=0x0021fdc0, int oparg=0)  行 3564 + 0x8f	C
python25.dll!PyEval_EvalFrameEx(_frame * f=0x00ba89e8, int throwflag=0)  行 2270	C
python25.dll!PyEval_EvalCodeEx(PyCodeObject * co=0x00bcae30, _object * globals=0x00ba89e8, _object * locals=0x00b7cdb0, _object * * args=0x00000000, int argcount=0, _object * * kws=0x00000000, int kwcount=0, _object * * defs=0x00000000, int defcount=0, _object * closure=0x00000000)  行 2831 + 0x8	C
python25.dll!PyEval_EvalCode(PyCodeObject * co=0x00bcae30, _object * globals=0x00b7cdb0, _object * locals=0x00b7cdb0)  行 499 + 0x22	C
python25.dll!run_mod(_mod * mod=0x00c48538, const char * filename=0x00bec770, _object * globals=0x00b7cdb0, _object * locals=0x00b7cdb0, PyCompilerFlags * flags=0xbdf20da3, _arena * arena=0x00000000)  行 1271 + 0x11	C
python25.dll!PyRun_FileExFlags(_iobuf * fp=0x7c3ab698, const char * filename=0x00ab3e4b, int start=257, _object * globals=0x00b7cdb0, _object * locals=0x00b7cdb0, int closeit=1, PyCompilerFlags * flags=0x0021ff1c)  行 1258	C
python25.dll!PyRun_SimpleFileExFlags(_iobuf * fp=0x7c3ab698, const char * filename=0x00ab3e4b, int closeit=1, PyCompilerFlags * flags=0x0021ff1c)  行 878 + 0x18	C
python25.dll!PyRun_AnyFileExFlags(_iobuf * fp=0x7c3ab698, const char * filename=0x00ab3e4b, int closeit=1, PyCompilerFlags * flags=0x0021ff1c)  行 696 + 0x11	C
python25.dll!Py_Main(int argc=2, char * * argv=0x00000001)  行 526 + 0x21	C
python.exe!1d0011a5() 	
kernel32.dll!7c816fd7() 	

This was already reported upstream at 
http://initd.org/tracker/pysqlite/ticket/205

It's a bug in the SQLite version of the DLL is shipped with Python 2.5 
on Windows. Updating the DLL to a newer version would help.

In the meantime, users can just download the newest DLL from the SQLite 
site and replace the one shipped by Python with it.

Ok, I'll modify the 2.5 maintenance line with this patch:
http://initd.org/tracker/pysqlite/changeset/426

Fixed in revision 59184.