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Why does NULL = NULL evaluate to false in SQL server
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Think of the null as "unknown" in that case (or "does not exist"). In either of those cases, you can't say that they are equal, because you don't know the value of either of them. So, null=null evaluates to not true (false or null, depending on you...
Should I use px or rem value units in my CSS? [closed]
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TL;DR: use px.
The Facts
First, it's extremely important to know that per spec, the CSS px unit does not equal one physical display pixel. This has always been true – even in the 1996 CSS 1 spec.
CSS defines the reference pixel, which measures the size of a pixel on a 96 dpi displa...
iPad keyboard will not dismiss if modal ViewController presentation style is UIModalPresentationForm
...eem to be a way to work around it.
UPDATE:
In iOS 4.3 and later, you can now implement `-disablesAutomaticKeyboardDismissal' on your view controller to return NO:
- (BOOL)disablesAutomaticKeyboardDismissal {
return NO;
}
This fixes the issue.
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Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
... relational table (STUDENT) with two columns and ID(int) and NAME(String). Now as ORM you would've made an entity class somewhat like as follows:-
package com.kashyap.default;
import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.G...
JavaScript: Check if mouse button down?
...ks more than one button intentionally or accidentally. Don't ask me how I know :-(.
The correct code should be like that:
var mouseDown = 0;
document.body.onmousedown = function() {
++mouseDown;
}
document.body.onmouseup = function() {
--mouseDown;
}
With the test like this:
if(mouseDown){...
Calendar date to yyyy-MM-dd format in java
... to override Date and provide your own implementation of Date.toString(). Now before you fire up your IDE and try this, I wouldn't; it will only complicate matters. You are better off formatting the date to the format you want to use (or display).
Java 8+
LocalDateTime ldt = LocalDateTime.now().p...
How to install PyQt4 on Windows using pip?
... "AMD64". To make it short: AMD's version was better and Intel adopted it, now calling it Intel64 for their CPUs - both are pretty much compatible (very minor differences). So pretty much every 64bit x86-64 CPU out there (except Itaniums) uses AMD64.
– user136036
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PostgreSQL: Drop PostgreSQL database through command line [closed]
...elect * from pg_stat_activity;" say? Are the other users besides yourself now connected? If so, you might have to edit your pg_hba.conf file to reject connections from other users, or shut down whatever app is accessing the pg database to be able to drop it. I have this problem on occasion in pro...
How set maximum date in datepicker dialog in android?
...ate picker maximum date is as today date according to system date.i don't know how to set date picker maximum date as today date.Can any one know help me to solve this problem.
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MySQL Removing Some Foreign keys
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This was my problem. I feel kind of dumb now. If anyone else has this problem, you can find the Foreign Key Constraint names by using the SHOW CREATE TABLE function.
– Drew
May 8 '09 at 6:06
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