Failure to initialize the variable can cause spurious non-zero
values.
http://msdn.microsoft.com/en-us/library/windows/desktop/ms715438(v=vs.85).aspx
"..value can either be a SQLULEN value or a null-terminated character
string. If the value is a SQLULEN value, some drivers may only write the
lower 32-bit or 16-bit of a buffer and leave the higher-order
bit unchanged. Therefore, applications should use a buffer of SQLULEN
and initialize the value to 0 before calling this function. Also, the
BufferLength and StringLengthPtr arguments are not used."
Follow-up to 1509316a37
Change-Id: I2e92eb845a2590bea0849c52bde8902adff1b419
Reviewed-by: Andy Shaw <andy.shaw@digia.com>
af35ee291a