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When should I use a composite index?
...d seperate and the third index is composite. As you can see you can search based on geolng on composite one since it is indexed by geolat, however it's possible to search by geolat or "geolat AND geolng" (since geolng is second level index).
Also, have a look at How MySQL Uses Indexes manual sectio...
Change the name of the :id parameter in Routing resources for Rails
...is winds up breaking the url helpers. They wind up generating a normal id based route if I pass an object in or complaining about a missing [:slug] key if I pass the slug in. Any ideas how to fix?
– RonLugge
Nov 30 '14 at 4:46
...
Which is more efficient, a for-each loop, or an iterator?
...the RandomAccess interface. The "C-style" loop is faster than the Iterator-based one. docs.oracle.com/javase/7/docs/api/java/util/RandomAccess.html
– andresp
Nov 20 '13 at 1:00
5
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Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
...ression to date has been that a DbContext is meant to represent your database, and thus, if your application uses one database, you'd want only one DbContext .
...
Ruby convert Object to Hash
...,v| hash[k] = v }
return hash
end
end
class Gift < ActiveRecord::Base
include ActiveRecordExtension
....
end
class Purchase < ActiveRecord::Base
include ActiveRecordExtension
....
end
and then just call
gift.to_hash()
purch.to_hash()
...
Java code To convert byte to Hexadecimal
...Convert 2 to Hex.
1) First convert 2 to binary in two's complement:
2 (base 10) = 0000 0010 (base 2)
2) Now convert binary to hex:
0000 = 0x0 in hex
0010 = 0x2 in hex
therefore 2 = 0000 0010 = 0x02.
Example 2: Convert -2 (in two's complement) to Hex.
1) First convert -2 to binary in two'...
Tomcat startup logs - SEVERE: Error filterStart how to get a stack trace?
...WEB-INF/classes with following content:
org.apache.catalina.core.ContainerBase.[Catalina].level = INFO
org.apache.catalina.core.ContainerBase.[Catalina].handlers = java.util.logging.ConsoleHandler
share
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Why does git-rebase give me merge conflicts when all I'm doing is squashing commits?
...hese commits by squashing many down into a single commit. Naturally, git-rebase seems the way to go. My problem is that it ends up with merge conflicts, and these conflicts are not easy to resolve. I don't understand why there should be any conflicts at all, since I'm just squashing commits (not del...
How do I log ALL exceptions globally for a C# MVC4 WebAPI app?
....Threading.CancellationToken cancellationToken)
{
var result = base.InvokeActionAsync(actionContext, cancellationToken);
if (result.Exception != null && result.Exception.GetBaseException() != null)
{
var baseException = result.Exception.GetBaseExcepti...
Making your .NET language step correctly in the debugger
...le, that will work just fine.
The JIT creates an implicit sequence point based on the following rules:
1. IL nop instructions
2. IL stack empty points
3. The IL instruction immediately following a call instruction
If it turns out we do need a repro to solve your issue, you can file...