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Find MongoDB records where array field is not empty
...lution:
ME.find({ pictures: { $exists: true, $ne: [] } })
Since MongoDB 2.6 release, you can compare with the operator $gt but could lead to unexpected results (you can find a detailled explanation in this answer):
ME.find({ pictures: { $gt: [] } })
...
Why is using 'eval' a bad practice?
...actice because eval and exec are frequently used in the wrong place.
EDIT 2:
It looks like some disagree that eval is 'very dangerous and insecure' in the OP case. That might be true for this specific case but not in general. The question was general and the reasons I listed are true for the gener...
Struct inheritance in C++
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297
Yes, struct is exactly like class except the default accessibility is public for struct (while...
Precision String Format Specifier In Swift
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288
My best solution so far, following from David's response:
import Foundation
extension Int {
...
What is the difference between Int and Integer?
...ers may
recognise the "bignum" type here.
"Int" is the more common 32 or 64 bit
integer. Implementations vary,
although it is guaranteed to be at
least 30 bits.
Source: The Haskell Wikibook. Also, you may find the Numbers section of A Gentle Introduction to Haskell useful.
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Multiple Type Constraints in Swift
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246
You can use a where clause which lets you specify as many requirements as you want (all of whi...
Installing pip packages to $HOME folder
...cal/lib/pythonx.y/site-packages/.
Note, that the above is true for Python 2.6. There has been a bit of controversy among the Python core developers about what is the appropriate directory location on Mac OS X for PEP370-style user installations. In Python 2.7 and 3.2, the location on Mac OS X was...
How to check for a valid Base64 encoded string
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William
19.3k88 gold badges4242 silver badges8787 bronze badges
answered Jun 10 '11 at 16:35
Anirudh RamanathanAnirudh Ramanathan...
Multiple commands in an alias for bash
...h }" ?
– emeraldjava
Jan 14 '10 at 12:12
2
How do you pass the argument? Nesting variable 'msg' ...
How can I find out the total physical memory (RAM) of my linux box suitable to be parsed by a shell
...ur use case, you might also want to know if the 8G in the system come from 2x4GB sticks or 4x2GB sticks.
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