A constant expression of type int with the value 0, or an expression of this type, cast to type void * is a null pointer constant, which if converted to a pointer becomes a null pointer. It is …

Apr 14, 2011 · Which is why you can only use IS NULL/IS NOT NULL as predicates for such situations. This behavior is not specific to SQL Server. All standards-compliant SQL dialects …

Feb 16, 2019 · null! is used to assign null to non-nullable variables, which is a way of promising that the variable won't be null when it is actually used. I'd use null! in a Visual Studio …

Mar 6, 2012 · The reasoning is that a null means "unknown", so the result of any comparison to a null is also "unknown". So you'll get no hit on rows by coding where my_column = null. SQL …

Jan 4, 2024 · Comparing null === 0 or null > 0 or null < 0 will result in false. But as null is also an object we can detect it as a null. I made a more complex function natureof witch will do better …

Apr 11, 2011 · That is one interpretaion of NULL. In certain contexts, it is clearly the correct one. But SQL is not consistent when it comes to NULL, so there are contexts where NULL means …

Dec 4, 2009 · The expression "NULL = NULL" evaluates to NULL, but is actually invalid in SQL; yet ORDER BY treats NULLs as equal (whatever they precede or follow "regular" values is left …

Feb 5, 2012 · @RogerWang - Good question! The answer is that null isn't an object, it's an object reference (a blank one). It's the only object reference we can write literally in code. So Object …

Apr 16, 2020 · Now IS NULL is a little trickier and is the preferred method for evaluating the condition of a variable being NULL. When you use the “IS NULL” clause, it checks both the …

Apr 25, 2010 · The null reference is the only possible value of an expression of null type. The null reference can always be cast to any reference type. In practice, the programmer can ignore …