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How do you query for “is not null” in Mongo?
...rue}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
db.mycollection.find({"IMAGE URL":{$ne:null}});
Also, according to the docs, $exists currently can't use an index, but $ne can.
Edit: Adding some examples due to interest in this answer
Given these inse...
Pull new updates from original GitHub repository into forked GitHub repository
I forked someone's repository on GitHub and would like to update my version with commits and updates made in the original repository. These were made after I forked my copy.
...
How to create a directory and give permission in single command
How to create a directory and give permission in single command in Linux?
8 Answers
8
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What's in an Eclipse .classpath/.project file?
...pse itself.
The .project file is maintained by the core Eclipse platform, and its goal is to describe the project from a generic, plugin-independent Eclipse view. What's the project's name? what other projects in the workspace does it refer to? What are the builders that are used in order to build ...
How can I distinguish whether Switch,Checkbox Value is changed by user or programmatically (includin
...meBoolean(checked);
}
});
Now you only pick up click events and don't have to worry about programmatic changes.
Answer 1:
I have created a wrapper class (see Decorator Pattern) which handles this problem in an encapsulated way:
public class BetterCheckBox extends CheckBox {
p...
UITextField border color
...rtzCore framework in you class:
#import <QuartzCore/QuartzCore.h>
and for changing the border color use the following code snippet (I'm setting it to redColor),
textField.layer.cornerRadius=8.0f;
textField.layer.masksToBounds=YES;
textField.layer.borderColor=[[UIColor redColor]...
How to make the 'cut' command treat same sequental delimiters as one?
...olumn-based, 'space'-adjusted text stream. I'm trying to use the cut command in the following manner:
5 Answers
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php var_dump() vs print_r()
What is the difference between var_dump() and print_r() in terms of spitting out an array as string?
12 Answers
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How to remove all line breaks from a string
I have a text in a textarea and I read it out using the .value attribute.
16 Answers
1...
Why do I get a warning icon when I add a reference to an MEF plugin project?
...test the core class of a plugin by directly referencing the plugin project and instantiating the plugin class. When I create a test Console App project and add a project reference to the plugin project, I get a warning icon (yellow triangle with exclamation mark) next to the reference in the Referen...