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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
... and index size in terms of bytes/MB/GB/etc , or even better the size for all tables. In Oracle I had a nasty long query that looked at user_lobs and user_segments to give back an answer.
...
Thread context switch Vs. process context switch
...that a context switch messes with the processors cacheing mechanisms. Basically, when you context switch, all of the memory addresses that the processor "remembers" in its cache effectively become useless. The one big distinction here is that when you change virtual memory spaces, the processor's Tr...
Replace a value if null or undefined in JavaScript
...owsers, ??=. This is equivalent to value = value ?? defaultValue.
||= and &&= are also coming, links below.
This checks if left side is undefined or null, short-circuiting if already defined. If not, the left side is assigned the right-side value.
Basic Examples
let a // undefined
l...
Autoreload of modules in IPython [duplicate]
Is there a way to have IPython automatically reload all changed code? Either before each line is executed in the shell or failing that when it is specifically requested to. I'm doing a lot of exploratory programming using IPython and SciPy and it's quite a pain to have to manually reload each module...
How to delete multiple values from a vector?
...ude it for the sake of readability.
This is, btw., what setdiff does internally (but without the unique to throw away duplicates in a which are not in remove).
If remove contains incomparables, you'll have to check for them individually, e.g.
if (any (is.na (remove)))
a <- a [! is.na (a)]
(...
How to pull a random record using Django's ORM?
...['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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How to use WeakReference in Java and Android development?
...t reference to protect the object from the garbage collector. A classic example is a cache that you want to be garbage collected when memory usage gets too high (often implemented with WeakHashMap).
Be sure to check out SoftReference and PhantomReference as well.
EDIT: Tom has raised some concern...
jQuery Validate Plugin - Trigger validation of single field
I've got a form that can optionally be pre-populated via facebook connect. Once a user connects, their name and email are automatically filled in. The problem is that this doesn't trigger the remote validation to check if the email already exists.
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How to get Linux console window width in Python
Is there a way in python to programmatically determine the width of the console? I mean the number of characters that fits in one line without wrapping, not the pixel width of the window.
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How do I enlarge an EER Diagram in MySQL Workbench?
... the Model pull-down there is an option Diagram Properties and Size, which allows the size of the diagram to be changed.
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