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How do you create a random string that's suitable for a session ID in PostgreSQL?
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random() gets called length times (like in many of the other solutions). Is there a more efficient way to choose from 62 characters each time? How does this perform compared to md5()?
– ma11hew28
Feb 1...
HTML5 textarea placeholder not appearing
...ayed since the input area contains content (a newline character is, technically, valid content).
Good:
<textarea></textarea>
Bad:
<textarea>
</textarea>
Update (2020)
This is not true anymore, according to the HTML5 parsing spec:
If the next token is a U+000A LINE FEED (LF)...
Abstract class in Java
...h the inheriting subclass must implement.
Provide a common interface which allows the subclass to be interchanged with all other subclasses.
Here's an example:
abstract public class AbstractClass
{
abstract public void abstractMethod();
public void implementedMethod() { System.out.print("...
When should I use the “strictfp” keyword in java?
I've looked up what this does, but does anyone actually have an example of when you would use the strictfp keyword in Java? Has anyone actually found a use for this?
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The name 'ConfigurationManager' does not exist in the current context
...you know why this has to be done when most other assemblies can simply be called by including the 'using' statement?
– Dhaust
Sep 2 '10 at 5:44
13
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What happens to a github student account's repositories at the end of 2 years?
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Ok, so the user can manually make the repo's public prior to or after the automatic downgrade if they do not desire to pay to access their code again.
– indivisible
Jun 23 '14 at 11:55
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Entity Framework: “Store update, insert, or delete statement affected an unexpected number of rows (
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That's a side-effect of a feature called optimistic concurrency.
Not 100% sure how to turn it on/off in Entity Framework but basically what it's telling you is that between when you grabbed the data out of the database and when you saved your changes someone ...
How to jQuery clone() and change id?
...D "klon4")
var $klon = $div.clone().prop('id', 'klon'+num );
// Finally insert $klon wherever you want
$div.after( $klon.text('klon'+num) );
});
<script src="https://code.jquery.com/jquery-3.1.0.js"></script>
<button id="cloneDiv">CLICK TO CLONE</button>
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Reorder / reset auto increment primary key
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You could drop the primary key column and re-create it. All the ids should then be reassigned in order.
However this is probably a bad idea in most situations. If you have other tables that have foreign keys to this table then it will definitely not work.
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Java Pass Method as Parameter
...out.println(data.toString());
}
}
public static void callCommand(Command command, Object data)
{
command.execute(data);
}
public static void main(String... args)
{
callCommand(new PrintCommand(), "hello world");
}
}
Edit: as Pete Kirkham ...