
What is the difference between NULL, '\0' and 0? - Stack Overflow
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 …
sql - Not equal <> != operator on NULL - Stack Overflow
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 …
c# - What does null! statement mean? - Stack Overflow
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 …
SQL is null and = null - Stack Overflow
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 …
How do I check for null values in JavaScript? - Stack Overflow
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 …
SQL Server: Null VS Empty String - Stack Overflow
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 …
Why does NULL = NULL evaluate to false in SQL server
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 …
language agnostic - What is the purpose of null? - Stack Overflow
Feb 25, 2009 · Also, the null character in a C-style variable length string is used to mark the end of the string. The use of null in these ways, especially for pointer values, has become so …
What's the difference between " = null" and " IS NULL"?
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 …
Java null check why use == instead of .equals() - Stack Overflow
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 …