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Postgres and Indexes on Foreign Keys and Primary Keys
...le, you will have an index on the PK and probably don't need to create any extra indexes.
While it's usually a good idea to create an index on (or including) your referencing-side foreign key columns, it isn't required. Each index you add slows DML operations down slightly, so you pay a performance...
How to select a single field for all documents in a MongoDB collection?
... include several fields. In the following operation, find() method returns all documents that match the query. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example ...
how do I use UIScrollView in Interface Builder?
...
eg setting the value to {320, 920} will let the user scroll down a whole extra screen on the iPhone.
(I am using xcode 4.3.3, the project's iOS Deployment Target is 5.1)
When I first did this I received the following error:
Illegal Configuration:
Size type user defined runtime a...
What is Prism for WPF?
...ed services for VM<->VM communication. It doesn't have some of the "extra" stuff provided by some MVVM "frameworks", such as a messaging framework, etc.
– Reed Copsey
Jun 9 '11 at 17:27
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Select elements by attribute in CSS
...r values with CSS only..
Attributes selectors allows you play around some extra with id and class attributes
Here is an awesome read on Attribute Selectors
Fiddle
a[href="http://aamirshahzad.net"][title="Aamir"] {
color: green;
text-decoration: none;
}
a[id*="google"] {
color: r...
SET NOCOUNT ON usage
... not have SET NOCOUNT OFF; and that is why they think they are not getting extra bytes in response. Accurate benchmark would be to use SET NOCOUNT ON in left and SET NOCOUNT OFF in right stored procedure. This way you will get TDS package with DONEINPROC (SET NOCOUNT ...), ten again DONEINPROC (INS...
How to generate all permutations of a list?
... in range(len(elements)):
# nb elements[0:1] works in both string and list contexts
yield perm[:i] + elements[0:1] + perm[i:]
A couple of alternative approaches are listed in the documentation of itertools.permutations. Here's one:
def permutations(iterable, r=None...
How to update a git clone --mirror?
...t remote update' does not in fact maintain the 'mirror' status without the extra operations mentioned there
– sehe
May 27 '11 at 12:26
1
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Relationship between SciPy and NumPy
SciPy appears to provide most (but not all [1]) of NumPy's functions in its own namespace. In other words, if there's a function named numpy.foo , there's almost certainly a scipy.foo . Most of the time, the two appear to be exactly the same, oftentimes even pointing to the same function object.
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Install go with brew, and running the gotour
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I had to put an extra bin/ on the end, since it seems now that they put these go executables into a subdirectory now. I.e., the command for my path is: export PATH=$PATH:/usr/local/Cellar/go/1.3.3/bin/bin/
– Nate
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