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Core Data: Quickest way to delete all instances of an entity
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Reset Entity in Swift 3 :
func resetAllRecords(in entity : String) // entity = Your_Entity_Name
{
let context = ( UIApplication.shared.delegate as! AppDelegate ).persistentContainer.viewContext
let deleteFetch = NSFetchRequest<NSFetchRequestResult>(entityNa...
How to find out if an installed Eclipse is 32 or 64 bit version?
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If your installation is 64-bit the string x86_ (which identifies a 32-bit installation) will still match. You need to look for x86_64_
– Leo
Jan 21 '13 at 15:54
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What is the difference between Ruby 1.8 and Ruby 1.9
...ements do not introduce scope in Ruby.
What's changed?
Single character strings.
Ruby 1.9
irb(main):001:0> ?c
=> "c"
Ruby 1.8.6
irb(main):001:0> ?c
=> 99
String index.
Ruby 1.9
irb(main):001:0> "cat"[1]
=> "a"
Ruby 1.8.6
irb(main):001:0> "cat"[1]
=> 97
{"...
PostgreSQL: insert from another table
...clause; they can be constant arithmetic expressions, for instance.
And a string literal is certainly a value expression.
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What is the optimal length for an email address in a database?
...s though.
Again, since a varchar only uses the space actually used by the string you store, there is no reason to have a small limit for email address length. Just go with 512 and stop worrying. Everything else is premature optimization
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linq where list contains any in list
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Or like this
class Movie
{
public string FilmName { get; set; }
public string Genre { get; set; }
}
...
var listofGenres = new List<string> { "action", "comedy" };
var Movies = new List<Movie> {new Movie {Genre="action", FilmName="Film1"},
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How to serialize a lambda?
...:
import java.io.Serializable;
public class Test {
static Object bar(String s) {
return "make serializable";
}
void m () {
SAM s1 = (SAM & Serializable) Test::bar;
SAM s2 = (SAM & Serializable) t -> "make serializable";
}
interface SAM {
...
How do you import a large MS SQL .sql file?
...e console app as a very last resort:
class Program
{
static void Main(string[] args)
{
RunScript();
}
private static void RunScript()
{
My_DataEntities db = new My_DataEntities();
string line;
System.IO.StreamReader file =
new System...
How to test chrome extensions?
...tabs.query({}, function(tabs) {
chrome.browserAction.setBadgeText({text: String(tabs.length)});
});
To test it we need:
mock chrome.tabs.query to return predefined response, e.g. two tabs.
inject our mocked chrome.* api into some environment
run our extension code in this environment
assert th...
How to make a round button?
...220dp"
android:background="@drawable/button_states"
android:text="@string/btn_scan_qr"
android:id="@+id/btn_scan_qr"
android:textSize="15dp"
/>
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