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How do you delete an ActiveRecord object?
...out a primary key
Note: from @hammady's comment, user.destroy won't work if User model has no primary key.
Note 2: From @pavel-chuchuva's comment, destroy_all with conditions and delete_all with conditions has been deprecated in Rails 5.1 - see guides.rubyonrails.org/5_1_release_notes.html
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Creating a BLOB from a Base64 string in JavaScript
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Will this still work if the size of the base64-encoded string is large, let's say larger than 665536 characters, which is the limit for URI sizes in Opera?
– Daniel Kats
Oct 24 '17 at 17:54
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Where Is Machine.Config?
...rop in replacements so don't have their own framework directories. Oh, and if you're unlucky enough to still be using .NET 1.1 then there may be a Framework/v1.1.4322 directory.
– Scott Lerch
May 19 '14 at 21:29
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Why doesn't delete set the pointer to NULL?
...setting of the pointer to NULL after delete is not part of the standard. If this gets taken care of then many of the crashes due to an invalid pointer would not occur. But having said that I can think of couple of reasons why the standard would have restricted this:
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Android: ScrollView force to bottom
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This doesn't work if the layout size has changed right before calling it. It needs to be posted instead.
– MLProgrammer-CiM
Apr 9 '15 at 15:32
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How do I determine if a port is open on a Windows server? [closed]
...rt may be closed by a firewall. Is there a way to ping out or in, on a specific port, to see if it is open?
13 Answers
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Peak-finding algorithm for Python/SciPy
...sed a (noisy) frequency-varying sinusoid on purpose because it shows many difficulties. We can see that the width parameter is not very useful here because if you set a minimum width too high, then it won't be able to track very close peaks in the high frequency part. If you set width too low, you w...
How to revert initial git commit?
...tial commit, but keeps all previously commited changes added to the index. If you want to also remove those changes, just execute a following git reset --hard. Even if incomplete, this answer is indeed the best one, so avoid using rm -fr .git (unless you know what you are doing).
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Using PowerShell credentials without being prompted for a password
... <any other parameters relevant to you>
You may need a different -Authentication switch value because I don't know your environment.
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How to select only the first rows for each unique value of a column
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A very simple answer if you say you don't care which address is used.
SELECT
CName, MIN(AddressLine)
FROM
MyTable
GROUP BY
CName
If you want the first according to, say, an "inserted" column then it's a different query
SELECT
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