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INSERT IF NOT EXISTS ELSE UPDATE?
... the ID column: In the replacement case the statement would set it to NULL and then a fresh ID would be allocated.
This approach can also be used if you want to leave particular field values alone if the row in the replacement case but set the field to NULL in the insert case.
For example, assumin...
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:
...
Switch statement fallthrough in C#?
... Damn - I've been programming with C# since the early days of 1.0, and I've never seen this until now. Just goes to show, you learn new things every day.
– Erik Forbes
Feb 5 '09 at 3:30
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WatiN or Selenium? [closed]
... tests of our presentation soon. It seems that everyone recommends WatiN and Selenium . Which do you prefer for automated testing of ASP.NET web forms? Which of these products work better for you?
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How to send data to local clipboard from a remote SSH session
...cting this thread because I've been looking for the same kind of solution, and I've found one that works for me. It's a minor modification to a suggestion from OSX Daily.
In my case, I use Terminal on my local OSX machine to connect to a linux server via SSH. Like the OP, I wanted to be able to tra...
What are the pros and cons of performing calculations in sql vs. in your application
...ed to access/aggregate a lot of data, doing it at the db server will save bandwidth, and disk io if the aggregates can be done inside indexes)
convenience (sql is not the best language for complex work - especially not great for procedural work, but very good for set-based work; lousy error-handling...
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...
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...
Regex: Specify “space or start of string” and “space or end of string”
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You can use any of the following:
\b #A word break and will work for both spaces and end of lines.
(^|\s) #the | means or. () is a capturing group.
/\b(stackoverflow)\b/
Also, if you don't want to include the space in your match, you can use lookbehind/aheads.
(?<=\...
What does the “yield” keyword do?
What is the use of the yield keyword in Python, and what does it do?
42 Answers
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