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Why are joins bad when considering scalability?
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...except in MySQL, which seems to have performance problems with large numbers of joins regardless of how your indexes look. Or at least it has in the past.
– Powerlord
Apr 12 '10 at 17:53
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Add a reference column migration in Rails 4
... Active Record only supports single column foreign keys and currently only mysql, mysql2 and PostgreSQL adapters are supported. Don't try this with other adapters like sqlite3, etc. Refer to Rails Guides: Foreign Keys for your reference.
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How to fix SSL certificate error when running Npm on Windows?
...s similar SSL problem a few days ago. The problem is your npm does not set root certificate for the certificate used by https://registry.npmjs.org.
Solutions:
Use wget https://registry.npmjs.org/coffee-script --ca-certificate=./DigiCertHighAssuranceEVRootCA.crt to fix wget problem
Use npm config...
Stopping an Android app from console
...s adb shell kill
That will only work for devices/emulators where you have root immediately upon running a shell. That can probably be refined slightly to call su beforehand.
Otherwise, you can do (manually, or I suppose scripted):
pc $ adb -d shell
android $ su
android # ps
android # kill <pro...
IntelliJ does not show project folders
...hat pops up, click on the "..." next button which takes you to the Content root. Find your root folder and select it
Click the "ok" button
Ignore any warning that says the name is already in use
share
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Get OS-level system information
... Runtime.getRuntime().totalMemory());
/* Get a list of all filesystem roots on this system */
File[] roots = File.listRoots();
/* For each filesystem root, print some info */
for (File root : roots) {
System.out.println("File system root: " + root.getAbsolutePath());
Sy...
Should I use px or rem value units in my CSS? [closed]
... <div> - 1.25px
The CSS3 rem, which is always relative only to the root html element, is now supported on 96% of all browsers in use.
The Opinion
I think everyone agrees that it's good to design your pages to be accommodating to everyone, and to make consideration for the visually impaire...
How to get root view controller?
I need an instance of root view controller.
7 Answers
7
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How to use count and group by at the same select statement
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needs alias otherwise wouldnt work in mysql. select count(*) from( ) agr
– amas
Jan 9 '14 at 6:54
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Getting root permissions on a file inside of vi? [closed]
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If you need root privileges to save a new file, replace % with the name (including path) of the new file.
– gvkv
Aug 10 '10 at 0:47
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