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How can I add a column that doesn't allow nulls in a Postgresql database?
...row. Not sure how Postgres locks up a table when doing this. Or, if column order matters, you can't just add a column with the ALTER command.
– alphadogg
Feb 5 '09 at 14:31
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dynamic_cast and static_cast in C++
...hic classes. In fact, in certian cases the classes must be polymorphic in order for the cast to be legal.
Casts can go in one of two directions: from base to derived (B2D) or from derived to base (D2B). It's simple enough to see how D2B casts would work at runtime. Either ptr was derived from T...
How do I link a JavaScript file to a HTML file?
... HTML document, ideally inside the which points to your javascript files. Order of the script tags are important. Load the jQuery before your script files if you want to use jQuery from your script.
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min...
Why is the Windows cmd.exe limited to 80 characters wide?
I love stretching my terminal on unix. What is the history or reason behind windows lame command line?
14 Answers
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How to handle button clicks using the XML onClick within Fragments
... could just do this:
Activity:
Fragment someFragment;
//...onCreate etc instantiating your fragments
public void myClickMethod(View v) {
someFragment.myClickMethod(v);
}
Fragment:
public void myClickMethod(View v) {
switch(v.getId()) {
// Just like you were doing
}
} ...
How to declare an array in Python?
...*The default built-in Python type is called a list, not an array. It is an ordered container of arbitrary length that can hold a heterogenous collection of objects (their types do not matter and can be freely mixed). This should not be confused with the array module, which offers a type closer to th...
What are the primary differences between Haskell and F#? [closed]
...apply code transformations more freely when it isn't bound to preserve the order of (unknown) side effects. In "encouraged purity" languages you write mostly similar code so the same optimizations would be applicable, only they might invalidate side effects (which aren't there, but the compiler can'...
Optimal number of threads per core
...
If your threads don't do I/O, synchronization, etc., and there's nothing else running, 1 thread per core will get you the best performance. However that very likely not the case. Adding more threads usually helps, but after some point, they cause some performance degradat...
MySQL Database won't start in XAMPP Manager-osx
...mputername>.local.pid)
My Solution:
In /Applications/XAMPP/xamppfiles/etc/my.cnf change user = <uid> s that <uid> is uid from id command.
$ id
uid=...
$ vim /Applications/XAMPP/xamppfiles/etc/my.cnf
...
s...
What does f+++++++++ mean in rsync logs?
...he item (such as the creation of a directory or the changing of a symlink, etc.).
A h means that the item is a hard link to another item (requires --hard-links).
A . means that the item is not being updated (though it might have attributes that are being modified).
A * means that the rest of the ite...