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Many-to-many relationship with the same model in rails?
...ails generates in the log file. You'll find something like the following:
SELECT * FROM "posts"
INNER JOIN "post_connections" ON "posts".id = "post_connections".post_b_id
WHERE ("post_connections".post_a_id = 1 )
To make the association bi-directional, we'd have to find a way to make Rails OR the...
The Use of Multiple JFrames: Good or Bad Practice? [closed]
...emo.). Good for:
Showing wizard like dialogs.
Displaying list, tree etc. selections for items that have an associated component.
Flipping between no component and visible component.
JInternalFrame/JDesktopPane typically used for an MDI.
JTabbedPane for groups of components.
JSplitPane A way to di...
Android Studio Project Structure (v.s. Eclipse Project Structure)
...
For android Studio 3.0.1 and selected all features:
Android O latest
Android Auto
Android things
Android wear
Android TV
C++ support
Kotlin support
The structure in version 3.0.1 does not look at all like all other answers.
Recent structure is as di...
How can I exclude all “permission denied” messages from “find”?
...ten to the file. The grep filters the standard output (you can decide how selective you want it to be, and may have to change the spelling depending on locale and O/S) and the final >&2 means that the surviving error messages (written to standard output) go to standard error once more. The f...
What is the difference between the kernel space and the user space?
...d 2 aren't used?
How is the current ring determined?
The current ring is selected by a combination of:
global descriptor table: a in-memory table of GDT entries, and each entry has a field Privl which encodes the ring.
The LGDT instruction sets the address to the current descriptor table.
See ...
What's the best way of scraping data from a website? [closed]
...y are already familiar with regexes. It's a huge mistake, use xpath or css selectors to navigate html and only use regular expressions to extract data from actual text inside an html node. This might already be obvious to you, it becomes obvious quickly if you try it but a lot of people waste a lot ...
Multi-key dictionary in c#? [duplicate]
...Values
from baseKey in baseDict.Keys
select baseDict[baseKey];
}
}
}
public class MultiKeyDictionary<K1, K2, K3, V> : Dictionary<K1, MultiKeyDictionary<K2, K3, V>> {
public V this[K1 key1, K2 key2, K3 key3] {
get {
...
Difference between Mock / Stub / Spy in Spock test framework
...ds that do real things. Can be used like a Stub to change return values of select methods. Can be used like a Mock to describe interactions.
def subscriber = Spy(SubscriberImpl, constructorArgs: ["Fred"])
def "should send message to subscriber"() {
when:
publisher.send("hello")
th...
How can building a heap be O(n) time complexity?
...ackward and calling siftDown. No matter which approach you choose, you are selecting the next item in the unsorted portion of the array and performing the appropriate operation to move it into a valid position in the ordered portion of the array. The only difference is performance.
...
What is a magic number, and why is it bad? [closed]
...Now, what you do is you have the 50 in different places - your SQL script (SELECT TOP 50 * FROM orders), your Website (Your Last 50 Orders), your order login (for (i = 0; i < 50; i++)) and possibly many other places.
Now, what happens when someone decides to change 50 to 25? or 75? or 153? You n...