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How to declare a variable in MySQL?
... refer to a variable that has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BET...
Avoiding if statement inside a for loop?
...e penalty.
The idea of passing in what varies is ubiquitous in the C++ Standard Library. It is called the strategy pattern.
If you are allowed to use C++11, you can do something like this:
#include <iostream>
#include <set>
#include <vector>
template <typename Container, ty...
What's the best way to store a group of constants that my program uses? [closed]
...I don't think I want an Enum , because the data is not all the same type, and I want to manually set each value. Should I just store them all in an empty class? Or is there a better way?
...
Debugging in Clojure? [closed]
...
There's also dotrace, which allows you to look at the inputs and outputs of selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (fib 3)
TRACE t4426: | (fib 2)
T...
Are C++ enums signed or unsigned?
Are C++ enums signed or unsigned? And by extension is it safe to validate an input by checking that it is = your min value (assuming you started at 0 and incremented by 1)?
...
Why am I seeing an “origin is not allowed by Access-Control-Allow-Origin” error here? [duplicate]
...quests outside of the current domain.
Ex 1: your domain is example.com and you want to make a request to test.com => you cannot.
Ex 2: your domain is example.com and you want to make a request to inner.example.com => you cannot.
Ex 3: your domain is example.com:80 and you want to make a...
Practical example where Tuple can be used in .Net 4.0?
...ng for the last 15 years. That's how expression bodied members were added, and now value tuples. Record-style classes narrowly missed the cut back in August (9 months before this comment) for this version of C# 7, and are probably coming out in C# 8. Also note that value tuples offer value equality ...
Redirecting from HTTP to HTTPS with PHP
I'm working on a shopping cart website and I would like to redirect the user to a HTTPS page when he's entering his billing details and maintain the HTTPS connection for the next pages until he logs out.
...
1052: Column 'id' in field list is ambiguous
I have 2 tables. tbl_names and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
...
How to name factory like methods?
...
Some random thoughts:
'Create' fits the feature better than most other words. The next best word I can think of off the top of my head is 'Construct'. In the past, 'Alloc' (allocate) might have been used in similar situations, re...