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JOIN queries vs multiple queries

...ase. It depends on a lot of things. Jeff Atwood (founder of this site) actually wrote about this. For the most part, though, if you have the right indexes and you properly do your JOINs it is usually going to be faster to do 1 trip than several. ...
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What is the difference between ng-if and ng-show/ng-hide

...he ng-if directive has one of the highest (if not the highest) priority of all Angular directives. Which means: it will run FIRST before all other, lower prioritised, directives. The fact that it runs FIRST, means that effectively, the element is removed before any inner directives are processed. Or...
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Unable to generate an explicit migration in entity framework

...the database OR you can delete the pending migration file ([201203170856167_left]) from your Migrations folder and then re-run "add-migration" to create a brand new migration based off of your edits. share | ...
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How do I edit /etc/sudoers from a script?

... Old thread, but what about: echo 'foobar ALL=(ALL:ALL) ALL' | sudo EDITOR='tee -a' visudo share | improve this answer | follow ...
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How to clear gradle cache?

...in your home directory, you will not want to delete the whole folder. Typically, just deleting .gradle/caches is enough to get Gradle to redownload all dependencies. – Bradford2000 Feb 9 '15 at 17:28 ...
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Dynamically load a JavaScript file

How can you reliably and dynamically load a JavaScript file? This will can be used to implement a module or component that when 'initialized' the component will dynamically load all needed JavaScript library scripts on demand. ...
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Code coverage with Mocha

...ul is. Try the following, after you get your mocha tests to pass: npm install nyc Now, simply place the command nyc in front of your existing test command, for example: { "scripts": { "test": "nyc mocha" } } sha...
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Joining two lists together

... No one's really gone into when to use which method. AddRange edits a list in place, adding the second list to it (as if you called .Add(foo) a bunch of times). The Concat and Union extension methods don't change the original list. They ...
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How to select rows from a DataFrame based on column values?

...have multiple values you want to include, put them in a list (or more generally, any iterable) and use isin: print(df.loc[df['B'].isin(['one','three'])]) yields A B C D 0 foo one 0 0 1 bar one 1 2 3 bar three 3 6 6 foo one 6 12 7 foo three 7 14 Note,...
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MySQL Removing Some Foreign keys

...You can use this to find foreign key constraints: SELECT * FROM information_schema.table_constraints WHERE constraint_schema = '<your db name>' AND constraint_type = 'FOREIGN KEY' – Gayan Dasanayake Aug 26 '17 at 2:48 ...