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“implements Runnable” vs “extends Thread” in Java
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Yes: implements Runnable is the preferred way to do it, IMO. You're not really specialising the thread's behaviour. You're just giving it something to run. That means composition is the philosophically "purer" way to go.
In practical terms, it means you can implement Runnable and extend from anot...
Why does 0.ToString(“#.##”) return an empty string instead of 0.00 or at least 0?
...nterestingly, if you do this: 0.ToString("#.0#"); you get: .0
If you want all three digits: 0.ToString("0.00"); produces: 0.00
From the comments to this answer, your argument seems to be,
it should show '0', because why would anyone ever want to see an empty string if the numeric value is 0?...
@property retain, assign, copy, nonatomic in Objective-C
...gners opted for the safer of the two solutions. In fact nonatomic is generally the better choice as it omits extremely expensive thread locks. The only reason to use atomic is if your property might be set from multiple threads (in which case omitting it can lead to an over-release or a leak).
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Swapping column values in MySQL
...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_test` (
`id` int(1...
Facebook database design?
...nd table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
Gender
DOB
Location
TableName: Friend...
What is choice_set in this Django app tutorial?
...jango's ORM follows the relationship backwards from Question too, automatically generating a field on each instance called foo_set where Foo is the model with a ForeignKey field to that model.
choice_set is a RelatedManager which can create querysets of Choice objects which relate to the Question i...
Use tnsnames.ora in Oracle SQL Developer
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I downloaded and installed the Oracle SQL Developer to connect to an already existing Oracle 11g database. But it seems that I will need to download and install Oracle client software also, which one do I use if I am on Windows 10?
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After installation of Gulp: “no command 'gulp' found”
After installing gulp.js via npm, I receive a no command 'gulp' found error when running the gulp command from the same directory it was installed into.
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How to reset radiobuttons in jQuery so that none is checked
...ethods, .attr and .prop to get distinguish between these situations.
.prop allows you to set a property on a DOM element, while .attr allows you to set an HTML attribute value. If you are working with plain DOM and set the checked property, elem.checked, to true or false you change the running value...
Clearing intent
My Android app is getting called by an intent that is passing information (pendingintent in statusbar).
20 Answers
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