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SQL “select where not in subquery” returns no results
...emantically the same.
When it is nullable, NOT IN is different, since IN (and, therefore, NOT IN) return NULL when a value does not match anything in a list containing a NULL.
This may be confusing but may become more obvious if we recall the alternate syntax for this:
common_id = ANY
(
SELECT c...
Avoiding SQL injection without parameters
...ametrized sql queries in our code. We have two sides in the discussion: Me and some others that say we should always use parameters to safeguard against sql injections and the other guys that don't think it is necessary. Instead they want to replace single apostrophes with two apostrophes in all str...
C# : 'is' keyword and checking for Not
...ublic static bool IsA<T>(this object obj) {
return obj is T;
}
and then use it to:
if (!child.IsA<IContainer>())
And you could follow on your theme:
public static bool IsNotAFreaking<T>(this object obj) {
return !(obj is T);
}
if (child.IsNotAFreaking<IContainer&g...
Can I use break to exit multiple nested 'for' loops?
...
AFAIK, C++ doesn't support naming loops, like Java and other languages do. You can use a goto, or create a flag value that you use. At the end of each loop check the flag value. If it is set to true, then you can break out of that iteration.
...
How to select between brackets (or quotes or …) in Vim?
...that I need it, I can't seem to find it (naturally), so I'll just ask nice and simple.
9 Answers
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Need for predictable random generator
I'm a web-game developer and I got a problem with random numbers. Let's say that a player has 20% chance to get a critical hit with his sword. That means, 1 out of 5 hits should be critical. The problem is I got very bad real life results — sometimes players get 3 crits in 5 hits, sometimes none i...
How can I check if multiplying two numbers in Java will cause an overflow?
I want to handle the special case where multiplying two numbers together causes an overflow. The code looks something like this:
...
How to escape the % (percent) sign in C's printf?
... this won't work. \045 is compile-time escape that is part of the language and will turn into % when compiled. printf is a run-time function, so it deals with bytes of your string, not with C source code, and it has its own escape sequences that are parts of the function. In short, printf is a "lang...
Is modern C++ becoming more prevalent? [closed]
...advanced topic, something you could learn about if you really wanted to. And there was certainly no one telling me that destructors could be harnessed to help manage memory.
Today, everywhere I look I see RAII and SFINAE and STL and Boost and, well, Modern C++. Even people who are just getting ...
Command to get nth line of STDOUT
Is there any bash command that will let you get the nth line of STDOUT?
13 Answers
13
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