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django models selecting single field
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thanks for the answer, what if I want to select only 1 or more fields (not all)?
– zentenk
Sep 21 '11 at 16:42
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Linq: GroupBy, Sum and Count
...a" is coming from, but the problem in the console app is that you're using SelectMany to look at each item in each group.
I think you just want:
List<ResultLine> result = Lines
.GroupBy(l => l.ProductCode)
.Select(cl => new ResultLine
{
ProductName =...
How do I fix the Visual Studio compile error, “mismatch between processor architecture”?
... item.
Find your project in the list, under Platform it will say "Any CPU"
Select the "Any CPU" option from the drop down and then select <New..>
From that dialog, select x86 from the "New Platform" drop down and make sure "Any CPU" is selected in the "Copy settings from" drop down.
Hit OK
You...
iOS: How to store username/password within an app?
... 3 right-click on frameworks folder and add existing framework. In Xcode 4 select your project, then select target, go to Build Phases tab and click + under Link Binary With Files) and KeychainItemWrapper .h & .m files into your project, #import the .h file wherever you need to use keychain and ...
How to select html nodes by ID with jquery when the id contains a dot?
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@Tomalak in comments:
since ID selectors must be preceded by a hash #, there should be no ambiguity here
“#id.class” is a valid selector that requires both an id and a separate class to match; it's valid and not always totally redundant.
The correct...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other ...
In PHP with PDO, how to check the final SQL parametrized query? [duplicate]
..... and finally EXECUTE ....
You won't be able to get some SQL string like SELECT * FROM ..., even if it would produce equivalent results, because no such query was ever actually sent to the database.
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Find CRLF in Notepad++
...h processes:
Simple search (Ctrl+F), Search Mode = Normal
You can select an EOL in the editing window.
Just move the cursor to the end of the line, and type Shift+Right Arrow.
or, to select EOL with the mouse, start just at the line end and drag to the start of the next line; dr...
Use LINQ to get items in one List, that are not in another List
...erride the equality:
var excludedIDs = new HashSet<int>(peopleList1.Select(p => p.ID));
var result = peopleList2.Where(p => !excludedIDs.Contains(p.ID));
This variant does not remove duplicates.
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AI2 Keep Awake
...Portal: Keeping your Android application running when the device wants to sleep . Table of contents Download Test results WakeLock WifiLock Battery optimization Foreground service Usage Request WakeLock Multiple WakeLocks Notification / Notification Channels NotificationChannel Noti...