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postgresql return 0 if returned value is null
...ns the first of its arguments that is not null.
Null is returned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cum...
Why does Java allow us to compile a class with a name different than the file name?
...
The rationale is to allow more than one top-level class per .java file.
Many classes—such as event listeners—are of local use only and the earliest versions of Java did not support nested classes. Without this relaxation of the "filename = ...
Properties order in Margin
...t two sizes like this:
Margin="1,2"
Left AND right
Top AND bottom
Finally you can specify a single size:
Margin="1"
used for all sides
The order is the same as in WinForms.
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impro...
Synchronise ScrollView scroll positions - android
...lview1"
... >
...
</com.test.ObservableScrollView>
Finally, we put it all together in the Layout class.
package com.test;
import android.app.Activity;
import android.os.Bundle;
public class Q3948934 extends Activity implements ScrollViewListener {
private ObservableScrol...
How to create user for a db in postgresql? [closed]
I have installed PostgreSQL 8.4 on my CentOS server and connected to root user from shell and accessing the PostgreSQL shell.
...
Preloading images with jQuery
...(see link). It looks like '$('<img src="' + this + '" />') would actually create the element within a hidden DIV, because it is more "complicated". However, I don't think this is needed for most browsers.
– JoshNaro
Feb 11 '11 at 15:30
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Why must wait() always be in synchronized block
We all know that in order to invoke Object.wait() , this call must be placed in synchronized block, otherwise an IllegalMonitorStateException is thrown. But what's the reason for making this restriction? I know that wait() releases the monitor, but why do we need to explicitly acquire the mon...
How do I remove objects from a JavaScript associative array?
...rray, if you do not want to create a sparsely populated array - and you usually don't - then you should use Array#splice or Array#pop.
Note that the delete operator in JavaScript does not directly free memory. Its purpose is to remove properties from objects. Of course, if a property being deleted ...
Angular js init ng-model from default values
...If fact, if you can get away from having your server render HTML entirely, all the better.
Ideally, you want to send out your Angular HTML templates, then pull down your values via $http in JSON and put them in your scope.
So if at all possible, do this:
app.controller('MyController', function($s...
Xcode 4 hangs at “Attaching to (app name)”
...n in the simulator or iOS device. It was working perfectly in Xcode 3, but all of a sudden now when I press run the program stops at "Attaching to...". There doesn't seem to be any other info to help with this problem either.
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