大约有 38,680 项符合查询结果（耗时：0.0378秒） [XML]
Check that Field Exists with MongoDB
..."1234"
"open":"Yes"
"things":{
"paper":1234
"bottle":"Available"
"bottle_count":40
}
}
We want to know if the bottle field is present or not?
Ans:
db.products.find({"things.bottle":{"$exists":true}})
...
How does a debugger work?
...dware debugging registers. Following is from that chapter:
T (trap) flag, TSS — Generates a debug exception (#DB) when an attempt is
made to switch to a task with the T flag set in its TSS.
I am not sure whether Window or Linux use this flag or not, but it is very interesting to read that chapte...
Performing Breadth First Search recursively
...= bfsNumForest(i+1, q)
val (bb, qqq) = qq.dequeue
val (aa, tss) = qqq.dequeue
tss.enqueue[org.dg.collection.BFSNumber.Tree[Int]](Node(i, aa, bb))
}
}
}
def bfsNumTree[T](t: Tree[T]): Tree[Int] = {
val q = Queue.Empty.enqueue[Tree[T]](t)
val qq = bfsNumForest(1, q)
...
Is there a “do … while” loop in Ruby?
... begin
n = 99
buf = ""
begin
buf << "#{n} bottles of beer on the wall\n"
# ...
n -= 1
end while n > 0
buf << "no more bottles of beer"
end
end
Originally written by Jeremy Voorhis. The content has been copied here because...
Install go with brew, and running the gotour
...ow/tab:
$ brew install go
==> Downloading https://homebrew.bintray.com/bottles/go-1.7.1.sierra.bottle.tar.gz
Already downloaded: /Users/nigel/Library/Caches/Homebrew/go-1.7.1.sierra.bottle.tar.gz
==> Pouring go-1.7.1.sierra.bottle.tar.gz
==> Caveats
As of go 1.2, a valid GOPATH is required...
Unresolved Import Issues with PyDev and Eclipse
... in the interpreter you are using in your project, in my case I was using "bottle" and the folder I added was "c:\Python33\Lib\site-packages\bottle-0.11.6-py3.3.egg"
Now I don't see the error anymore, and the code completion feature works as well with "bottle".
...
How do I convert CamelCase into human-readable names in Java?
...mple XML Parser]
"GL11Version", // [GL 11 Version]
"99Bottles", // [99 Bottles]
"May5", // [May 5]
"BFG9000", // [BFG 9000]
};
for (String test : tests) {
System.out.println("[" + splitCamelCase(test) + "]");
}
It...
How to implement a queue using two stacks?
...st In First Out (LIFO) in computer science.
Lets imagine our stack like a bottle as below;
If we push integers 1,2,3 respectively, then 3 will be on the top of the stack. Because 1 will be pushed first, then 2 will be put on the top of 1. Lastly, 3 will be put on the top of the stack and latest ...
facebook: permanent Page Access Token?
..."accounts" does not exist, even for v2.7: https://graph.facebook.com/v2.7/{page_id}?fields=access_token&access_token={long_lived_access_token}
– Reado
Jul 23 '16 at 9:07
...
What is the correct way to start a mongod service on linux / OS X?
...e.
$ brew install mongodb
==> Downloading https://homebrew.bintray.com/bottles/mongodb-3.0.6.yosemite.bottle.tar.gz ### 100.0%
==> Pouring mongodb-3.0.6.yosemite.bottle.tar.gz
==> Caveats
To have launchd start mongodb at login:
ln -sfv /usr/local/opt/mongodb/*.plist ~/Library/LaunchAgent...