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How to declare variable and use it in the same Oracle SQL script?
...nd variable. The mechanism for assigning values to a VAR is with an EXEC call:
SQL> var name varchar2(20)
SQL> exec :name := 'SALES'
PL/SQL procedure successfully completed.
SQL> select * from dept
2 where dname = :name
3 /
DEPTNO DNAME LOC
---------- -------------- ...
How to get a subset of a javascript object's properties
...og(picked); // { a: 5, c: 7 }
From Philipp Kewisch:
This is really just an anonymous function being called instantly. All of this can be found on the Destructuring Assignment page on MDN. Here is an expanded form
let unwrap = ({a, c}) => ({a, c});
let unwrap2 = function({a, ...
What is the difference between typeof and instanceof and when should one be used vs. the other?
...
@Luke generally a bad idea to use "new String" like this. that creates a "string object" rather than a string primitive. see section here developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Colin D
...
Skip first entry in for loop in python?
...
Not for all iterables, but for all sequences.
– Sven Marnach
Apr 9 '12 at 20:27
2
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What is The Rule of Three?
...in various contexts,
and we should understand what "copying an object" actually means.
Let us consider a simple example:
class person
{
std::string name;
int age;
public:
person(const std::string& name, int age) : name(name), age(age)
{
}
};
int main()
{
person a("Bjar...
How to add “active” class to Html.ActionLink in ASP.NET MVC
...ges, it would be smart to have a way to apply that selected class automatically based on the current page rather than copy the menu multiple times and do it manually.
The easiest way is to simply use the values contained in ViewContext.RouteData, namely the Action and Controller values. We could b...
Getting jQuery to recognise .change() in IE
...Pacifika: Not for me in IE7. At least it gets that right. "click" is a totally different event from "change" and there are at least some cases (if not all) where it's an inappropriate substitute.
– Bobby Jack
Jul 9 '09 at 11:27
...
Why is semicolon allowed in this python snippet?
...ot warrant the use of semicolons to end statements.
So why is this (below) allowed?
15 Answers
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Checking for NULL pointer in C/C++ [closed]
In a recent code review, a contributor is trying to enforce that all NULL checks on pointers be performed in the following manner:
...
How to rename a single column in a data.frame?
...r.name'
This code pretty much does the following:
names(df) looks into all the names in the df
[names(df) == old.var.name] extracts the variable name you want to check
<- 'new.var.name' assigns the new variable name.
...