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How to change collation of database, table, column?
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You need to either convert each table individually:
ALTER TABLE mytable CONVERT TO CHARACTER SET utf8mb4
(this will convert the columns just as well), or export the database with latin1 and import it back with utf8mb4.
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How to delete all Annotations on a MKMapView
Is there a simple way to delete all the annotations on a map without iterating through all the displayed annotations in Objective-c?
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Error in Swift class: Property not initialized at super.init call
...error:”
Safety check 1 “A designated initializer must ensure that all of the
“properties introduced by its class are initialized before it
delegates up to a superclass initializer.”
Excerpt From: Apple Inc. “The Swift Programming Language.” iBooks.
https://itunes.apple.co...
How to implement an abstract class in ruby?
I know there is no concept of abstract class in ruby. But if at all it needs to be implemented, how to go about it? I tried something like...
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In which situations do we need to write the __autoreleasing ownership qualifier under ARC?
...ents that are passed by reference (id *) and are autoreleased on return.
All of this is very well explained in the ARC transition guide.
In your NSError example, the declaration means __strong, implicitly:
NSError * e = nil;
Will be transformed to:
NSError * __strong error = nil;
When you c...
Disable individual Python unit tests temporarily
... so. You could just get this module and use it on your existing Python install. It will probably work.
Before this, I used to rename the tests I wanted skipped to xtest_testname from test_testname.
Here's a quick elisp script to do this. My elisp is a little rusty so I apologise in advance for ...
PHP mkdir: Permission denied problem
...te permissions on the directory.
Here's what you do in Ubuntu
Make sure all files are owned by the Apache group and user. In Ubuntu it is the www-data group and user
chown -R www-data:www-data /path/to/webserver/www
Next enabled all members of the www-data group to read and write files
chmod -R...
Counting the number of elements with the values of x in a vector
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Don't forget about potential floating point issues, especially with table, which coerces numbers to strings.
– hadley
Dec 17 '09 at 18:10
4
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How do I dump an object's fields to the console?
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Adding an inspect method to your class allows you to define how the class' attributes are displayed, rather than rely on default output. A lot of classes don't implement it well, but it can be really useful when debugging. Ruby will fall back to to_s if it can't f...
Number of elements in a javascript object
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Although JS implementations might keep track of such a value internally, there's no standard way to get it.
In the past, Mozilla's Javascript variant exposed the non-standard __count__, but it has been removed with version 1.8.5.
For cross-browser scripting you're stuck with explicitly ite...