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What are naming conventions for MongoDB?
...tation mentions you may use underscores, also built-in identifier is named _id (but this may be be to indicate that _id is intended to be private, internal, never displayed or edited.
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impro...
Best way to merge two maps and sum the values of same key?
...leads to arguably the shortest/cleanest solution:
scala> import scalaz._
import scalaz._
scala> import Scalaz._
import Scalaz._
scala> val map1 = Map(1 -> 9 , 2 -> 20)
map1: scala.collection.immutable.Map[Int,Int] = Map(1 -> 9, 2 -> 20)
scala> val map2 = Map(1 -> 100, ...
What is your preferred style for naming variables in R? [closed]
...e full paper is here:
http://journal.r-project.org/archive/2012-2/RJournal_2012-2_Baaaath.pdf
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SQL- Ignore case while searching for a string
...
Use something like this -
SELECT DISTINCT COL_NAME FROM myTable WHERE UPPER(COL_NAME) LIKE UPPER('%PriceOrder%')
or
SELECT DISTINCT COL_NAME FROM myTable WHERE LOWER(COL_NAME) LIKE LOWER('%PriceOrder%')
...
WARN Could not determine content-length of response body. Set content-length of the response or set
...d of Webrick, and the warn will disappear.
– fearless_fool
Aug 3 '12 at 3:55
2
I second using thi...
Set value to NULL in MySQL
... can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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...
How do you send a HEAD HTTP request in Python 2?
...rt urllib2
>>> class HeadRequest(urllib2.Request):
... def get_method(self):
... return "HEAD"
...
>>> response = urllib2.urlopen(HeadRequest("http://google.com/index.html"))
Headers are available via response.info() as before. Interestingly, you can find the URL th...
How do I declare an array of weak references in Swift?
...T] {
return objects.flatMap { $0.object }
}
func contains(_ object: T) -> Bool {
return self.objects.contains(WeakObject(object: object))
}
func addObject(_ object: T) {
self.objects.formUnion([WeakObject(object: object)])
}
func addObjects(_ obj...
New self vs. new static
...the first method, whereas static is bound to the called class (also see get_called_class()).
class A {
public static function get_self() {
return new self();
}
public static function get_static() {
return new static();
}
}
class B extends A {}
echo get_class(B::ge...
使用TokuMX配置Replica Set集群 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...e，可加参数指定ip、端口，默认本机27017）
config={
"_id" : "ReplSetName",
"members" : [
{"_id" : 0, "host" : "172.16.88.97:27017",priority:2},
{"_id" : 1, "host" : "172.16.88.97:27018",priority:1},
{"_id" : 2, "host" : "172.16.88.97:27019",arbit...