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Rails: Why does find(id) raise an exception in rails? [duplicate]
If there is no user with an id of 1 in the database, trying User.find(1) will raise an exception.
2 Answers
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Sequence contains more than one element
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SingleOrDefault method throws an Exception if there is more than one element in the sequence.
Apparently, your query in GetCustomer is finding more than one match. So you will either need to refine your query or, most likely, check your data to see why you're gettin...
What's the best way to bundle static resources in a Go program? [closed]
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Embedding Text Files
If we're talking about text files, they can easily be embedded in the source code itself. Just use the back quotes to declare the string literal like this:
const html = `
<html>
<body>Example embedded HTML conten...
count the frequency that a value occurs in a dataframe column
...38]:
df['a'].value_counts()
Out[38]:
b 3
a 2
s 2
dtype: int64
If you wanted to add frequency back to the original dataframe use transform to return an aligned index:
In [41]:
df['freq'] = df.groupby('a')['a'].transform('count')
df
Out[41]:
a freq
0 a 2
1 b 3
2 s 2
3 s...
How to set a selected option of a dropdown list control using angular JS
... a selected option of a dropdown list control using angular JS. Forgive me if this is ridiculous but I am new with Angular JS
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Using Git, show all commits that are in one branch, but not the other(s)
... to my current branch which have not been applied to any other branch [or, if this is not possible without some scripting, how does one see all commits in one branch which have not been applied to another given branch?].
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How to get a number of random elements from an array?
...ew Array(n),
len = arr.length,
taken = new Array(len);
if (n > len)
throw new RangeError("getRandom: more elements taken than available");
while (n--) {
var x = Math.floor(Math.random() * len);
result[n] = arr[x in taken ? taken[x] : x];
tak...
How to switch to the new browser window, which opens after click on the button?
...Handle);
}
// Perform the actions on new window
// Close the new window, if that window no more required
driver.close();
// Switch back to original browser (first window)
driver.switchTo().window(winHandleBefore);
// Continue with original browser (first window)
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Regular expression for a hexadecimal number?
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That could be shortified to /0x[\da-f]/i, but otherwise, +1.
– Niklas B.
Feb 10 '12 at 1:13
20
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Index of Currently Selected Row in DataGridView
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If it's anything like Excel, the selected list can be many rows/columns, but there is only one current/active cell. I only care about the current row so this should do fine.
– ErikE
Aug ...