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How to COUNT rows within EntityFramework without loading contents?
... where o.ID == '1'
from t in o.MyTable
select t).Count();
Method syntax:
var count = context.MyContainer
.Where(o => o.ID == '1')
.SelectMany(o => o.MyTable)
.Count()
Both generate the same SQL query.
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Xcode 6 Bug: Unknown class in Interface Builder file
... this issue when using Xcode 6 beta 4.
To resolve this issue, you need to select each of your custom class objects in Storyboard (this includes any custom views, even the custom view controllers themselves).
Then with those objects selected, open the identity inspector and under "Custom Class" you...
Android file chooser [closed]
...ent in an Intent.createChooser() like this:
private static final int FILE_SELECT_CODE = 0;
private void showFileChooser() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
try {
startActivityForR...
unable to copy/paste in mingw shell
...
Right-click on the title bar of the command window and select 'Properties', then on the 'Options' tab tick the box for the 'QuickEdit mode', then click 'Ok'.
After that you can paste text from the clipboard using the right mouse-button, highlight text while holding down the left...
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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How to do what head, tail, more, less, sed do in Powershell? [closed]
...option for reading a text file. You can then filter further:
gc log.txt | select -first 10 # head
gc -TotalCount 10 log.txt # also head
gc log.txt | select -last 10 # tail
gc -Tail 10 log.txt # also tail (since PSv3), also much faster than above option
gc log.txt | more #...
“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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SQL Server: Difference between PARTITION BY and GROUP BY
...y're used in different places. group by modifies the entire query, like:
select customerId, count(*) as orderCount
from Orders
group by customerId
But partition by just works on a window function, like row_number:
select row_number() over (partition by customerId order by orderId)
as OrderN...
What is the relative performance difference of if/else versus switch statement in Java?
... just ints. From the Java Tutorials: "A switch works with the byte, short, char, and int primitive data types. It also works with enumerated types (discussed in Enum Types), the String class, and a few special classes that wrap certain primitive types: Character, Byte, Short, and Integer (discussed ...
Difference between open and codecs.open in Python
...get is why open sometimes can handle very well the UTF-8 encoded non-latin characters of the unicode set, and sometimes it fails miserabily ...
– cedbeu
Mar 27 '13 at 18:45
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