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Swapping column values in MySQL
...work:
UPDATE swap_test s1, swap_test s2 SET s1.x=s1.y, s1.y=s2.x WHERE s1.id=s2.id;
Essentially, the 1st table is the one getting updated and the 2nd one is used to pull the old data from.
Note that this approach requires a primary key to be present.
This is my test schema:
CREATE TABLE `swap_t...
Aligning a float:left div to center?
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you may need to add vertical-align:middle while using display:inline-block.
– ibsenv
May 24 '15 at 10:59
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What does “@private” mean in Objective-C?
... to clarify, methods are always public in Objective-C. There are ways of "hiding" method declarations, though—see this question for more information.
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Deleting a Google App Engine application
...ine SDK 1.2.6 it's possible to delete apps completely. But beware, the app-id won't be usable again.
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Why do some websites add “Slugs” to the end of URLs? [closed]
...ssing" I think the minority is extremely tiny.
– eyelidlessness
Jun 2 '09 at 15:59
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@eyelidlessn...
Javascript/jQuery: Set Values (Selection) in a multiple Select
...lue='" + e + "']").prop("selected", true);
});
Working Example http://jsfiddle.net/McddQ/1/
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Is there a print_r or var_dump equivalent in Ruby / Ruby on Rails?
...1
updated_at: 2009-05-26 22:46:29.501245
current_login_ip: 127.0.0.1
id: "1"
current_login_at: 2009-05-24 20:20:46.627254
login_count: "1"
last_login_ip:
last_login_at:
login: admin
attributes_cache: {}
=> nil
>>
If you want to just preview some string contents, try us...
Show or hide element in React
... around with React.js for the first time and cannot find a way to show or hide something on a page via click event. I am not loading any other library to the page, so I am looking for some native way using the React library. This is what I have so far. I would like to show the results div when th...
Rails 4 - Strong Parameters - Nested Objects
... the other hand if you want nested of multiple objects then you wrap it inside a hash… like this
params.require(:foo).permit(:bar, {:baz => [:x, :y]})
Rails actually have pretty good documentation on this: http://api.rubyonrails.org/classes/ActionController/Parameters.html#method-i-permit
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MongoDB with redis
...the collection level (to be used for purging data for instance).
Redis provides a convenient set datatype and its associated operations (union, intersection, difference on multiple sets, etc ...). It is quite easy to implement a basic faceted search or tagging engine on top of this feature, which is...