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List columns with indexes in PostgreSQL
...
Create some test data...
create table test (a int, b int, c int, constraint pk_test primary key(a, b));
create table test2 (a int, b int, c int, constraint uk_test2 unique (b, c));
create table test3 (a int, b int, c int, constraint uk_test3b unique (b), constraint uk_te...
How to pass a function as a parameter in Java? [duplicate]
...Java 8 and above
Using Java 8+ lambda expressions, if you have a class or interface with only a single abstract method (sometimes called a SAM type), for example:
public interface MyInterface {
String doSomething(int param1, String param2);
}
then anywhere where MyInterface is used, you can ...
Can PostgreSQL index array columns?
...ators and the GIN-index type.
Example:
CREATE TABLE "Test"("Column1" int[]);
INSERT INTO "Test" VALUES ('{10, 15, 20}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because we have only 2 records...
Getting current unixtimestamp using Moment.js
...to get the Unix TimeStamp using Moment.js.
I can find many functions which convert timestamp to date in moment.js.
I know that I can easily get the unix timestamp by using the following JavaScript function: Math.floor(new Date().getTime()/1000) .
...
Using arrays or std::vectors in C++, what's the performance gap?
...sing the array around will lose any information about its size (array to pointer conversion). You should use boost::array in that case, which wraps a C++ array in a small class and provides a size function and iterators to iterate over it.
Now the std::vector vs. native C++ arrays (taken from the i...
No ConcurrentList in .Net 4.0?
... (also: on GitHub). My implementation had some problems, which I won't get into here. Let me tell you, more importantly, what I learned.
Firstly, there's no way you're going to get a full implementation of IList<T> that is lockless and thread-safe. In particular, random insertions and removal...
Creating a blocking Queue in .NET?
...readonly Queue<T> queue = new Queue<T>();
private readonly int maxSize;
public SizeQueue(int maxSize) { this.maxSize = maxSize; }
public void Enqueue(T item)
{
lock (queue)
{
while (queue.Count >= maxSize)
{
Moni...
ASP.NET MVC Custom Error Handling Application_Error Global.asax?
...EM RELATIVE TO WHERE YOUR CSPROJ FILE IS!
var requestControllerName = Convert.ToString(HttpContext.Current.Request.RequestContext?.RouteData?.Values["controller"]);
var requestActionName = Convert.ToString(HttpContext.Current.Request.RequestContext?.RouteData?.Values["action"]);
var co...
Retrieve column names from java.sql.ResultSet
...column count starting at 1. You can iterate through column names with for (int i = 1; i <= rsmd.getColumnCount(); i++) String name = rsmd.getColumnName(i);
– Alphaaa
Nov 19 '15 at 7:03
...
What is JavaScript's highest integer value that a number can go to without losing precision?
...
JavaScript has two number types: Number and BigInt.
The most frequently-used number type, Number, is a 64-bit floating point IEEE 754 number.
The largest exact integral value of this type is Number.MAX_SAFE_INTEGER, which is:
253-1, or
+/- 9,007,199,254,740,991, or...