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What is a “surrogate pair” in Java?
...mething about surrogate pairs . What is a surrogate pair in this context? And what are low and high surrogates?
7 An...
CROSS JOIN vs INNER JOIN in SQL
What is the difference between CROSS JOIN and INNER JOIN ?
12 Answers
12
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pandas: multiple conditions while indexing data frame - unexpected behavior
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As you can see, the AND operator drops every row in which at least one
value equals -1. On the other hand, the OR operator requires both
values to be equal to -1 to drop them.
That's right. Remember that you're writing the condition in te...
Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
5 Answers
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How can I remove a character from a string using Javascript?
...ing.replace(/\/r/g, '/');
EDIT:
Since everyone's having so much fun here and user1293504 doesn't seem to be coming back any time soon to answer clarifying questions, here's a method to remove the Nth character from a string:
String.prototype.removeCharAt = function (i) {
var tmp = this.split(...
PDOException SQLSTATE[HY000] [2002] No such file or directory
...basic) site to fortrabbit, but as soon as I connect to SSH to run some commands (such as php artisan migrate or php artisan db:seed ) I get an error message:
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When should I use @classmethod and when def method(self)?
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Your guess is correct - you understand how classmethods work.
The why is that these methods can be called both on an instance OR on the class (in both cases, the class object will be passed as the first argument):
class Dummy(object):
@classmethod
d...
What is the difference between square brackets and parentheses in a regex?
.../^[789]\d{9}$/
/^[7-9]\d{9}$/
The explanation:
(a|b|c) is a regex "OR" and means "a or b or c", although the presence of brackets, necessary for the OR, also captures the digit. To be strictly equivalent, you would code (?:7|8|9) to make it a non capturing group.
[abc] is a "character class" th...
Dependency Injection vs Factory Pattern
... when it comes to usage/design the difference between dependency injection and factory is blurred or thin.
28 Answers
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How to use git bisect?
...les saying that git bisect is awesome. However, I'm not a native speaker and I can't understand why it's awesome.
6 Answe...