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MySQL: Quick breakdown of the types of joins [duplicate]
...planation of the join type
JOIN: Return rows when there is at least one match in both tables
LEFT JOIN: Return all rows from the left table, even if there are no matches in the right table
RIGHT JOIN: Return all rows from the right table, even if there are no matches in the left table
F...
How to change legend title in ggplot
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p$labels$fill is nice but if you are using more than one variable in aesthetic (linetype, color, shape) in aes, you have to change them for each separately.
– discipulus
Dec 9 '16 at 1:19
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Best Practice for Exception Handling in a Windows Forms Application?
... things simple.
Exception handling in .NET is more art than science. Everyone will have their favorites to share here. These are just a few of the tips I've picked up using .NET since day 1, techniques which have saved my bacon on more than one occasion. Your mileage may vary.
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Copy constructor versus Clone()
...t is the preferred way to add (deep) copy functionality to a class? Should one implement the copy constructor, or rather derive from ICloneable and implement the Clone() method?
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How can I import one Gradle script into another?
...ings.gradle you actually point to your subprojects:
include 'my-first-component',
'my-second-component'
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project(':my-first-component').projectDir = new File(rootDir, 'path/to/first/component')
project(':my-second-component').projectDir = new File(rootDir, 'path/to/second/component')
......
Why is iostream::eof inside a loop condition (i.e. `while (!stream.eof())`) considered wrong?
...g ints or std::strings or similar, the EOF bit is set when you extract the one right before the end and the extraction hits the end. You do not need to read again. The reason it doesn't get set when reading from files is because there's an extra \n at the end. I've covered this in another answer. Re...
The simplest possible JavaScript countdown timer? [closed]
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I have two demos, one with jQuery and one without. Neither use date functions and are about as simple as it gets.
Demo with vanilla JavaScript
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
set...
Getting the last element of a list
...his answer is incorrect. Getting a list when you want an element only postpones the inevitable "list index out of range" - and that's what should happen when attempting to get an element from an empty list. For Strings astr[-1:] could be a valid approach since it returns the same type as astr[-1], b...
Most tricky/useful commands for gdb debugger [closed]
...ceeding through subroutine calls.
* reverse-nexti ('rni') -- Step backward one instruction, but proceed through called subroutines.
* reverse-step ('rs') -- Step program backward until it reaches the beginning of a previous source line
* reverse-stepi -- Step backward exactly one instruction
* set e...
How to rollback a specific migration?
...1
Is a way to do this, if the migration you want to rollback is the last one applied. You can substitute 1 for however many migrations you want to go back.
For example:
rake db:rollback STEP=5
Will also rollback all the migration that happened later (4, 3, 2 and also 1).
To roll back all migr...