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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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is it possible to select EXISTS directly as a bit?
I was wondering if it's possible to do something like this (which doesn't work):
9 Answers
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What is the size of column of int(11) in mysql in bytes?
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An INT will always be 4 bytes no matter what length is specified.
TINYINT = 1 byte (8 bit)
SMALLINT = 2 bytes (16 bit)
MEDIUMINT = 3 bytes (24 bit)
INT = 4 bytes (32 bit)
BIGINT = 8 bytes (64 bit).
The length just specifies how many characters to pad when selecting data with the ...
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 can I get device ID for Admob
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If you are running admob ads on an emulator then there is no ID. just use the AdManager method and set it to TEST_EMULATOR like the logcat says. If you run on an actual device with usb debugging and watch the logcat, the ID...
Android List Preferences: have summary as selected value?
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@BaptisteCandellier thanks for the heads-up. If something exists, the Android team will deprecate it. I've added a link to androidx.
– George Hilliard
Jul 1 '19 at 22:02
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PHP shell_exec() vs exec()
I'm struggling to understand the difference between shell_exec() and exec() ...
4 Answers
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In Objective-C, what is the equivalent of Java's “instanceof” keyword?
...bject ) is assignable (cast-able) to a variable of another type (e.g. SpecifiedType ). In Java, I can write:
3 Answers
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Simple tool to 'accept theirs' or 'accept mine' on a whole file using git
...it upsteam and is coming back to me through a pull, but may be slightly modified in various places.
5 Answers
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How to conditionally push an item in an observable array?
I would like to push a new item onto an observableArray , but only if the item is not already present. Is there any "find" function or recommended pattern for achieving this in KnockoutJS?
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