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How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
How to customize the background/border colors of a grouped table view cell?
...later UITableViewCell now has a backgroundColor property that makes this really easy (especially in combination with the [UIColor colorWithPatternImage:] initializer). But I'll leave the 2.0 version of the answer here for anyone that needs it…
It's harder than it really should be. Here's how I ...
How to redirect 404 errors to a page in ExpressJS?
...isionmedia/express/blob/master/examples/error-pages/index.js
So it is actually this part:
// "app.router" positions our routes
// above the middleware defined below,
// this means that Express will attempt
// to match & call routes _before_ continuing
// on, at which point we assume it's a 404...
Why is TypedReference behind the scenes? It's so fast and safe… almost magical!
...ecification, the constructs used to implement them under the hood (vararg calling convention, TypedReference type, arglist, refanytype, mkanyref, and refanyval instructions) are perfectly documented in the CLI Specification (ECMA-335) in the Vararg library.
Being defined in the Vararg Library makes ...
Find rows that have the same value on a column in MySQL
...LECT email,
count(*) AS c
FROM TABLE
GROUP BY email
HAVING c > 1
ORDER BY c DESC
If you want the full rows:
select * from table where email in (
select email from table
group by email having count(*) > 1
)
...
How to specify different Debug/Release output directories in QMake .pro file
...ke things even easier to switch around, only define your DESTDIRs conditionally, and then use that value in all your other paths: OBJECTS_DIR = $${DESTDIR}/.obj. Cheers!
– Xavier Holt
Mar 7 '12 at 4:16
...
The multi-part identifier could not be bound
...GROUP BY maxa
) AS dkcd ON dkcd.maxa = a.maxa
WHERE a.maxa <> '99'
ORDER BY a.maxa
Here the tables a and b are joined first, then the result is joined to dkcd. Basically, this is the same query as yours, only using a different syntax for one of the joins, which makes a great difference: th...
source of historical stock data [closed]
...hat will not get you very far.
Then, if you need the real stuff (level II order book, all ticks as they have happened at all exchanges) one "affordable", yet excellent option is Nanex. They'll actually ship you a drive with terabytes of data. If I remember right its about $3k-4K per year of data. B...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
... retaining the copy.
Assign
Assign is somewhat the opposite to copy. When calling the getter of an assign property, it returns a reference to the actual data. Typically you use this attribute when you have a property of primitive type (float, int, BOOL...)
Retain
retain is required when the attribut...
What does “connection reset by peer” mean?
...cognize the connection; it will send back a packet with the RST bit set in order to forcibly close the connection.
This can happen if the other side crashes and then comes back up or if it calls close() on the socket while there is data from you in transit, and is an indication to you that some o...