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How do you query for “is not null” in Mongo?
...n empty string which means "", it will be returned.It is the same behavior for
db.collection_name.find({"filed_name":{$ne:null}});
Extra validation:
Okay, so we are not finished yet we need an extra condition.
db.collection_name.
find({ "field_name":{$type:2},$where:"this.field_name.length >...
How can I remove an element from a list, with lodash?
...ause you can use a predicate function, which is exactly what I was looking for. Removing an element is trivial if you know the index, but what about when you don't know the index?
– random_user_name
Jan 19 '16 at 23:30
...
What do querySelectorAll and getElementsBy* methods return?
...h a real array:
var elems = document.getElementsByClassName('myElement');
for(var i = 0; i < elems.length; i++) {
elems[i].style.size = '100px';
}
If you prefer something shorter, consider using jQuery:
$('.myElement').css('size', '100px');
...
pandas GroupBy columns with NaN (missing) values
...in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fillna(-1).groupby('b').sum()
Out[12]:
a
b
-1...
What is the difference between Serializable and Externalizable in Java?
...ntating java.io.Serializable, you get "automatic" serialization capability for objects of your class. No need to implement any other logic, it'll just work. The Java runtime will use reflection to figure out how to marshal and unmarshal your objects.
In earlier version of Java, reflection was very ...
I want to use CASE statement to update some records in sql server 2005
The statement work for the purpose but the else condition scan through every record in the table. Is there any way I can leave the unaffected rows as they are?
...
How to correctly use “section” tag in HTML5?
...ections of a thesis. A Web site's
home page could be split into sections for an introduction, news
items, and contact information.
Authors are encouraged to use the article element instead of the
section element when it would make sense to syndicate the contents of
the element.
The...
Automatically resize jQuery UI dialog to the width of the content loaded by ajax
I'm having a lot of trouble finding specific information and examples on this. I've got a number of jQuery UI dialogs in my application attached to divs that are loaded with .ajax() calls. They all use the same setup call:
...
How to autosize a textarea using Prototype?
I'm currently working on an internal sales application for the company I work for, and I've got a form that allows the user to change the delivery address.
...
How to change the type of a field?
...
The only way to change the $type of the data is to perform an update on the data where the data has the correct type.
In this case, it looks like you're trying to change the $type from 1 (double) to 2 (string).
So simply load the document from the DB, perform the cast (new Str...