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How do I automatically update a timestamp in PostgreSQL
...update_modified_column()
RETURNS TRIGGER AS $$
BEGIN
NEW.modified = now();
RETURN NEW;
END;
$$ language 'plpgsql';
Apply the trigger like this:
CREATE TRIGGER update_customer_modtime BEFORE UPDATE ON customer FOR EACH ROW EXECUTE PROCEDURE update_modified_column();
...
Is there a way to change the spacing between legend items in ggplot2?
...
Now that opts is deprecated in ggplot2 package, function theme should be used instead:
library(grid) # for unit()
... + theme(legend.key.height=unit(3,"line"))
... + theme(legend.key.width=unit(3,"line"))
...
What is Inversion of Control?
...SpellChecker(); // dependency
TextEditor textEditor = new TextEditor(sc);
Now the client creating the TextEditor class has control over which SpellChecker implementation to use because we're injecting the dependency into the TextEditor signature.
...
Constant Amortized Time
... up in a room.
And, you have long hands and legs, as much long as you need now or in future.
And, you have to fill all in one room, so it is easy to lock it.
So, you go right to the end/ corner of the room and start stacking them.
As you stack them, slowly the room will run out of space.
However, a...
How to keep a git branch in sync with master
.... That was written by the Git maintainer, so it's probably fair to say he knows what he's talking about with regard to this particular topic.
– Dan Moulding
Mar 12 '14 at 23:44
2
...
How to delete a module in Android Studio
... record of the project app folder(Check it by clcking on the Gradle View). Now go to File->Close Project.
Step 3: Now you are at the start window. Move the cursor on the in recent project list. Press Delete.
Step 4: Delete the folder from the explorer by moving or deleting it actually. This lo...
How do I package a python application to make it pip-installable?
...
'django-profiles',
'django-uni-forms',
],
Obviously now we have two places where dependencies are defined, but that doesn't necessarily mean that these information are duplicated: setup.py vs requirements.txt
With this setup your package should be installable via pip.
As ...
How do I determine the size of my array in C?
...;
size_t n = sizeof(a) / sizeof(a[0]);
Another advantage is that you can now easily parameterize
the array name in a macro and get:
#define NELEMS(x) (sizeof(x) / sizeof((x)[0]))
int a[17];
size_t n = NELEMS(a);
share
...
How do I insert a linebreak where the cursor is without entering into insert mode in Vim?
...stion in the subject, instead of the one in the posting. What he wants to know is how to easily get rid of the whitespace that was at the point where the line was broken but no longer serves a purpose.
– Aristotle Pagaltzis
Oct 26 '08 at 3:27
...
What does the construct x = x || y mean?
...hy; otherwise you'd get "Neither x nor y is truthy".
The actual question
Now, when you know how || operator works, you can probably make out by yourself what does x = x || y mean. If x is truthy, x is assigned to x, so actually nothing happens; otherwise y is assigned to x. It is commonly used to ...