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How to use NULL or empty string in SQL
I would like to know how to use NULL and an empty string at the same time in a WHERE clause in SQL Server. I need to find records that have either null values or an empty string. Thanks.
...
What's the difference between a file descriptor and file pointer?
...LE Structure returned by fopen
typedef struct
{
unsigned char *_ptr;
int _cnt;
unsigned char *_base;
unsigned char *_bufendp;
short _flag;
short _file;
int __stdioid;
char *__newbase;
#ifdef _THREAD_SAFE
...
Why don't structs support inheritance?
...Basically, they're supposed to hold simple data and therefore do not have "extra features" such as inheritance. It would probably be technically possible for them to support some limited kind of inheritance (not polymorphism, due to them being on the stack), but I believe it is also a design choice ...
Are there any downsides to passing structs by value in C, rather than passing a pointer?
...e output parameters be listed first before input parameters, e.g. int func(char* out, char *in);
– zooropa
Apr 29 '09 at 12:29
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Compare DATETIME and DATE ignoring time portion
...ng, contrived example.
--112 is ISO format 'YYYYMMDD'
declare @filterDate char(8) = CONVERT(char(8), GETDATE(), 112)
select
*
from
Sales.Orders
where
CONVERT(char(8), OrderDate, 112) = @filterDate
In a perfect world, performing any manipulation to the filtered column should be avo...
Does delete on a pointer to a subclass call the base class destructor?
...n this will happen when the containing object is destroyed.
class A
{
char *someHeapMemory;
public:
A() : someHeapMemory(new char[1000]) {}
~A() { delete[] someHeapMemory; }
};
class B
{
A* APtr;
public:
B() : APtr(new A()) {}
~B() { delete APtr; }
};
class C
{
A Amemb...
How to combine paths in Java?
...
Rather than keeping everything string-based, you should use a class which is designed to represent a file system path.
If you're using Java 7 or Java 8, you should strongly consider using java.nio.file.Path; Path.resolve can be used to combine one path wi...
How to index characters in a Golang string?
...
Interpreted string literals are character sequences between double quotes "" using the (possibly multi-byte) UTF-8 encoding of individual characters. In UTF-8, ASCII characters are single-byte corresponding to the first 128 Unicode chara...
Difference between a Structure and a Union
...re that value.
union foo {
int a; // can't use both a and b at once
char b;
} foo;
struct bar {
int a; // can use both a and b simultaneously
char b;
} bar;
union foo x;
x.a = 3; // OK
x.b = 'c'; // NO! this affects the value of x.a!
struct bar y;
y.a = 3; // OK
y.b = 'c'; // OK
ed...
Why does Git treat this text file as a binary file?
...ut need of a null (00h) byte for anything other than the nul char (the 'C' string terminator). Thus Git's text definition is that the content (well the first 1k bytes) should not have a null byte when utf-8 encoded. Try stackoverflow.com/questions/2241348/… for a fun read. My original comment ref...