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Does List guarantee insertion order?
...
The List<> class does guarantee ordering - things will be retained in the list in the order you add them, including duplicates, unless you explicitly sort the list.
According to MSDN:
...List "Represents a strongly typed list of objects that can be
a...
selecting unique values from a column
...se the DISTINCT operator in MySQL:
SELECT DISTINCT(Date) AS Date FROM buy ORDER BY Date DESC;
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z-index not working with fixed positioning
...side a stacking context and you will see that elements are stacked in this order
The stacking context’s root element (the <html> element in this case)
Positioned elements (and their children) with negative z-index values (higher values are stacked in front of lower values; elements ...
Code First: Independent associations vs. Foreign key associations?
...l advantage of ORM you will definitely use Entity reference:
public class Order
{
public int ID { get; set; }
public Customer Customer { get; set; } // <-- Customer object
...
}
Once you generate an entity model from a database with FKs it will always generate entity references. If...
Concat scripts in order with Gulp
... project on Backbone or whatever and you need to load scripts in a certain order, e.g. underscore.js needs to be loaded before backbone.js .
...
How do I sort a dictionary by value?
...representation of a dictionary that is sorted. Dictionaries are inherently orderless, but other types, such as lists and tuples, are not. So you need an ordered data type to represent sorted values, which will be a list—probably a list of tuples.
For instance,
import operator
x = {1: 2, 3: 4, 4: 3...
When should a class be Comparable and/or Comparator?
...ct. The class itself must implements the java.lang.Comparable interface in order to be able to compare its instances.
Comparator
A comparator object is capable of comparing two different objects. The class is not comparing its instances, but some other class’s instances. This comparator class mu...
How to simplify a null-safe compareTo() implementation?
...gt; NULL_SAFE_COMPARATOR
= new NullComparator(String.CASE_INSENSITIVE_ORDER);
@Override
public int compareTo(Metadata other) {
int result = NULL_SAFE_COMPARATOR.compare(this.name, other.name);
if (result != 0) {
return result;
}
return NULL_SAFE_COMPARATOR.compare(this....
Error message “Forbidden You don't have permission to access / on this server” [closed]
...is rule:
IF MATCHED BY BOTH, THE LAST DIRECTIVE IS THE ONE THAT WILL WIN
Order allow,deny
Deny will win if matched by both directives (even if an allow directive is written after the deny in the conf)
Order deny,allow
allow will win if matched by both directives
Example 1
Order allow,deny
All...
How to select the nth row in a SQL database table?
...dard windowing functions:
SELECT * FROM (
SELECT
ROW_NUMBER() OVER (ORDER BY key ASC) AS rownumber,
columns
FROM tablename
) AS foo
WHERE rownumber <= n
(which I just copied from the site linked above since I never use those DBs)
Update: As of PostgreSQL 8.4 the standard windowing...