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- c# - What does null! statement mean? - Stack Overflow
It can be used on a type to control Nullability, it is then called the "Null Forgiving Operator" Basically, null! applies the ! operator to the value null This overrides the nullability of the value null to non-nullable, telling the compiler that null is a "non-null" type
- SQL is null and = null - Stack Overflow
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 provides the special syntax for testing if a column is null, via is null and is not null, which is a special condition to test for a null (or not a null)
- javascript - Why is null an object and whats the difference between . . .
In order to be able to query this difference, JavaScript has null and undefined: While null is - just like in other languages an object, undefined cannot be an object because there is no instance (even not a null instance) available
- What is the difference between NULL, \0 and 0? - Stack Overflow
In C, there appear to be differences between various values of zero -- NULL, NUL and 0 I know that the ASCII character '0' evaluates to 48 or 0x30 The NULL pointer is usually defined as: #define
- Why does NULL = NULL evaluate to false in SQL server
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 to DBMS vendor)
- Whats the difference between = null and IS NULL?
Understanding the difference between “IS NULL” and “= NULL” When a variable is created in SQL with the declare statement it is created with no data and stored in the variable table (vtable) inside SQLs memory space The vtable contains the name and memory address of the variable
- sql - Not equal lt; gt; != operator on NULL - Stack Overflow
135 NULL has no value, and so cannot be compared using the scalar value operators In other words, no value can ever be equal to (or not equal to) NULL because NULL has no value Hence, SQL has special IS NULL and IS NOT NULL predicates for dealing with NULL
- Java null check why use == instead of . equals () - Stack Overflow
In Java I am told that when doing a null check one should use == instead of equals() What are the reasons for this?
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