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How to concatenate text from multiple rows into a single text string in SQL server?
... answer.
I had a similar issue when I was trying to join two tables with one-to-many relationships. In SQL 2005 I found that XML PATH method can handle the concatenation of the rows very easily.
If there is a table called STUDENTS
SubjectID StudentName
---------- -------------
1 ...
What does Maven do, in theory and in practice? When is it worth to use it? [closed]
...'t get issues as having the same code with the same buildscript working on one computer but not on another one (this is a known issue, we have VMs of Windows 98 machines since we couldn't get some of our Delphi applications compiling anywhere else). Because of this, it is also the best way to work o...
round() for float in C++
...
There's no round() in the C++98 standard library. You can write one yourself though. The following is an implementation of round-half-up:
double round(double d)
{
return floor(d + 0.5);
}
The probable reason there is no round function in the C++98 standard library is that it can in f...
How do I use Nant/Ant naming patterns?
...ore characters across directory levels
a question mark (?) matches exactly one character within a path name
Another way to think about it is double star (**) matches slash (/) but single star (*) does not.
Let's say you have the files:
bar.txt
src/bar.c
src/baz.c
src/test/bartest.c
Then the p...
Intent - if activity is running, bring it to front, else start a new one (from notification)
...ivities in the app and this is the parent, singleInstance if you have only one Activity.
– frostymarvelous
May 21 '16 at 15:49
4
...
Round a double to 2 decimal places [duplicate]
...o, use this instead
(Adapted from this answer by Louis Wasserman and this one by Sean Owen.)
public static double round(double value, int places) {
if (places < 0) throw new IllegalArgumentException();
BigDecimal bd = BigDecimal.valueOf(value);
bd = bd.setScale(places, RoundingMode...
What is the best algorithm for overriding GetHashCode?
...) == XorHash(y, x) for all x, y
By the way, the earlier algorithm is the one currently used by the C# compiler for anonymous types.
This page gives quite a few options. I think for most cases the above is "good enough" and it's incredibly easy to remember and get right. The FNV alternative is sim...
ActiveRecord.find(array_of_ids), preserving order
...
Oddly, no one has suggested something like this:
index = Something.find(array_of_ids).group_by(&:id)
array_of_ids.map { |i| index[i].first }
As efficient as it gets besides letting SQL backend do it.
Edit: To improve on my own ...
How do I create a new GitHub repo from a branch in an existing repo?
...at you don't need to create a repo on Github, you can just push to a local one (i.e. git init instead of Github > New > ...)
– OJFord
Apr 19 '16 at 12:19
1
...
Using an integer as a key in an associative array in JavaScript
...vier to initialize.
Here is an example:
const map = new Map();
map.set(1, "One");
map.set(2, "Two");
map.set(3, "Three");
console.log("=== With Map ===");
for (const [key, value] of map) {
console.log(`${key}: ${value} (${typeof(key)})`);
}
console.log("=== With Object ===");
const fakeMap =...