大约有 48,000 项符合查询结果（耗时：0.0516秒） [XML]
find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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How to only get file name with Linux 'find'?
I'm using find to all files in directory, so I get a list of paths. However, I need only file names. i.e. I get ./dir1/dir2/file.txt and I want to get file.txt
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Bin size in Matplotlib (Histogram)
...hat value before?
– UserYmY
Sep 29 '15 at 13:25
1
I believe binwidth in this example could be fou...
How to retrieve checkboxes values in jQuery
...t works (see the example):
function updateTextArea() {
var allVals = [];
$('#c_b :checked').each(function() {
allVals.push($(this).val());
});
$('#t').val(allVals);
}
$(function() {
$('#c_b input').click(updateTextArea);
updateTextArea();
});
Update
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How to check if a value exists in a dictionary (python)
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it wasn't necesarry after all, unless run on bigger dict. I guess overhead in values() is caused by copying the value list and in viewvalues() by maintaining the view alive.
– soulcheck
Nov 21 '11 at 17:12
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How do I write LINQ's .Skip(1000).Take(100) in pure SQL?
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But this will first select all and then from that selection take only 10 right? Or will the first query/view have only 10 already?
– Tadej
Jan 29 '18 at 13:53
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How to sign an android apk file
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https://developer.android.com/studio/publish/app-signing.html
Okay, a small overview without reference or eclipse around, so leave some space for errors, but it works like this
Open your project in eclipse
Press right-mouse - > tools (android tools?) - > export signed application (apk?)
G...
Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'
... sign of quality design.
IOStreams have a checkered history. They are actually a reworking of an earlier streams library, but were authored at a time when many of today's C++ idioms didn't exist, so the designers didn't have the benefit of hindsight. One issue that only became apparent over time wa...
What is a stored procedure?
... a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples.
To create a stored procedure the syntax is fairly simple:
CRE...
Samples of Scala and Java code where Scala code looks simpler/has fewer lines?
I need some code samples (and I also really curious about them) of Scala and Java code which show that Scala code is more simple and concise then code written in Java (of course both samples should solve the same problem).
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