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How do I partially update an object in MongoDB so the new object will overlay / merge with the exist
Given this document saved in MongoDB
17 Answers
17
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Using a piano keyboard as a computer keyboard [closed]
...ed 30 different computer keyboards which all caused me pain. Playing piano does not cause me pain. I have played piano for around 20 years without any pain issues. I would like to know if there is a way to capture MIDI from a MIDI keyboard and output keyboard strokes. I know nothing at all about MID...
Disable back button in android
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Override the onBackPressed method and do nothing if you meant to handle the back button on the device.
@Override
public void onBackPressed() {
if (shouldAllowBack()) {
super.onBackPressed();
} else {
doSomething();
}
}
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PSQLException: current transaction is aborted, commands ignored until end of transaction block
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I got this error using Java and PostgreSQL doing an insert on a table. I will illustrate how you can reproduce this error:
org.postgresql.util.PSQLException: ERROR:
current transaction is aborted, commands ignored until end of transaction block
Summary:
The reason ...
Echo a blank (empty) line to the console from a Windows batch file [duplicate]
When outputting status messages to the console from a Windows batch file, I want to output blank lines to break up the output. How do I do this?
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What's the recommended approach to resetting migration history using Django South?
...the baseline and start a fresh set of migrations. I've reviewed the South documentation , done the usual Google/Stackoverflow searching (e.g. "django south (reset OR delete OR remove) migration history") and haven't found anything obvious.
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How to delete history of last 10 commands in shell?
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If you do this with vim you may find your deletion history in ~/.viminfo so be sure to remove that too!
– waltwood
Jul 22 '15 at 22:39
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How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
db.my...
How do I set the size of an HTML text box?
How do I set the size of an HTML text box?
11 Answers
11
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Abstract functions in Swift Language
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There no concept of abstract in Swift (like Objective-C) but you can do this :
class BaseClass {
func abstractFunction() {
preconditionFailure("This method must be overridden")
}
}
class SubClass : BaseClass {
override func abstractFunction() {
// Override
...