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mysql create user if not exists
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I use
SELECT EXISTS (SELECT DISTINCT user FROM mysql.user WHERE user = "username") as is_user
should return 1 if exists or 0 if it does not
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How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
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“A project with an Output type of Class Library cannot be started directly”
...oject in Solution Explorer -> Properties.
In opened tab with properties select Application and there will be ComboBox marked with Output Type label.
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The server principal is not able to access the database under the current security context in SQL Se
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DECLARE @UserName nvarchar(255)
DECLARE orphanuser_cur cursor for
SELECT UserName = su.name
FROM sysusers su
JOIN sys.server_principals sp ON sp.name = su.name
WHERE issqluser = 1 AND
(su.sid IS NOT NULL AND su.sid <> 0x0) AND
suser_sname(su....
How to delete multiple files at once in Bash on Linux?
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Just use multiline selection in sublime to combine all of the files into a single line and add a space between each file name and then add rm at the beginning of the list. This is mostly useful when there isn't a pattern in the filenames you wa...
LINQ Select Distinct with Anonymous Types
...DelegateComparer<T>(equals,null));
}
}
var uniqueItems=students.Select(s=> new {FirstName=s.FirstName, LastName=s.LastName})
.Distinct((a,b) => a.FirstName==b.FirstName, c => c.FirstName.GetHashCode()).ToList();
Sorry for the messed up formatting earlier
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How to change package name of an Android Application
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Right-click on the package name (src/com.android.gesture.builder).
Select Refactor > Rename and change the name, for example to
com.android.gestureNEW.builder.
Open the manifest file. Inside the
<manifest> tag, change the package name to
com.android.gestureNEW.builder.
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How to remove all rows in a numpy.ndarray that contain non-numeric values
... @naught101 You also need to change any to all. Since you want to select rows where "all are finite", instead of selecting rows where "not any are nan".
– AnnanFay
Jun 6 '17 at 4:59
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How to change package name of Android Project in Eclipse?
...can rename or change the package name, and also by right-clicking and then select Rename option, you can change or rename the package name.
When you press F2, it will show you the dialog box as:
In this dialog, don't forget to check the "Update references" checkbox because by making "check" to t...
How to find all duplicate from a List? [duplicate]
...d then filter out any of the enumerables that have a Count of <=1, then select their keys to get back down to a single enumerable:
var duplicateKeys = list.GroupBy(x => x)
.Where(group => group.Count() > 1)
.Select(group => group.Key);
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