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Remove duplicated rows using dplyr
...ce(from = 1, to = 1)
Or maybe a variation of unique() that would let you select which
variables to use:
df %>% unique(x, y)
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Entity Framework: table without primary key
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
answered Apr 26 '10 at 17:00 by Tillito
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How to merge a list of lists with same type of items to a single list of items?
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Use the SelectMany extension method
list = listOfList.SelectMany(x => x).ToList();
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Do I have to guard against SQL injection if I used a dropdown?
...
$size = filter_input(INPUT_POST, "size", FILTER_VALIDATE_INT);
echo '<select name="size">';
foreach($sizes as $i => $s) {
echo '<option value="' . $i . '"' . ($i == $size ? ' selected' : '') . '>' . $s . '</option>';
}
echo '</select>';
Then you can use $size in yo...
VIM Ctrl-V Conflict with Windows Paste
...nce CTRLV is used to paste, you can't use it to start a blockwise Visual
selection. You can use CTRLQ instead. You can also use CTRLQ in Insert
mode and Command-line mode to get the old meaning of CTRLV. But CTRLQ
doesn't work for terminals when it's used for control flow.
...
How can I get “Copy to Output Directory” to work with Unit Tests?
... In VS2010 this is: Test/Edit Test Settings/local, then in the list, select "Deployment", check the "Enable..." box and add the file(s).
– Marcel
Jun 16 '10 at 12:54
18
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How to simulate Android killing my process
...at window in Android Studio (this will kill the app process, make sure you select your device and process in Logcat dropdowns at top)
Get back to the application with Home long press or opened apps (depends on the device)
Application will start in recreated ActivityD (ActivityA, ActivityB, ActivityC...
How to enable Ad Hoc Distributed Queries
...ded
sp_configure 'Ad Hoc Distributed Queries', 1;
RECONFIGURE;
GO
SELECT a.*
FROM OPENROWSET('SQLNCLI', 'Server=Seattle1;Trusted_Connection=yes;',
'SELECT GroupName, Name, DepartmentID
FROM AdventureWorks2012.HumanResources.Department
ORDER BY GroupName, Name') AS a;
GO
O...
Update ViewPager dynamically?
...ybe some example please!!! i have a listview with list of cities and after selecting city opens viewpager (3 pages) with information about this city. it works ok. but after selecting another city viewpager shows only the 3d page on refreshes the 1-st page only after swiping pages? thw 2d page is alw...
How to make all Objects in AWS S3 bucket public by default?
...n.s3.amazonaws.com/policygen.html
Fill in the details such as:
In Action select "GetObject"
Select "Add Statement"
Then select "Generate Policy"
Copy the text example:
{
"Id": "Policy1397632521960",
"Statement": [
{
"Sid": "Stmt1397633323327",
"Action": [
"s3:GetObjec...