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The null (ish) coalescing operator only works with null and undefined. So, use the null (ish) coalescing operator when you don't want those values but you will otherwise accept other falsy …
14 de abr. de 2011 · 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 …
5 de feb. de 2012 · In Java I am told that when doing a null check one should use == instead of .equals(). What are the reasons for this?
1 de may. de 2010 · 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 …
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: …
21 de sept. de 2021 · The only difference (besides the syntax) is, that the compiler guarantees that no user-overloaded operator is called when using is not null instead of != null (or is null …
And then == null does a perfect job, because it covers exactly those 2 values. (i.e. == null is equivalent to === null && === undefined) In exceptional cases you do want a clear distinction …
16 de feb. de 2019 · 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 …
4 de dic. de 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 …
6 de mar. de 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 …
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