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How to get values from IGrouping
...th>();
IEnumerable<IGrouping<int, smth>> groups = list.GroupBy(x => x.id);
IEnumerable<smth> smths = groups.SelectMany(group => group);
List<smth> newList = smths.ToList();
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Insert, on duplicate update in PostgreSQL?
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the 'where' part can be simplified by using exists: ... where not exists (select 1 from table where id = 3);
– Endy Tjahjono
Oct 21 '11 at 6:46
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Insert Update stored proc on SQL Server
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The best strategy is to attempt the
update. If no rows are affected by the
update then insert. In most
circumstances, the row will already
exist and only one I/O will be
required.
Edit:
Please check out this answer and the linked blog post to learn about the problems with this patt...
How to exclude a module from a Maven reactor build?
...r will take in account the order in 'modules', although the order dictated by dependencies is of a higher priority.
– hellodanylo
Jul 29 '13 at 11:23
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mongodb count num of distinct values per field/key
...is example of using aggregation API. To complicate the case we're grouping by case-insensitive words from array property of the document.
db.articles.aggregate([
{
$match: {
keywords: { $not: {$size: 0} }
}
},
{ $unwind: "$keywords" },
{
$group: {...
When to use EntityManager.find() vs EntityManager.getReference() with JPA
...Ronald what happens if there is a Version annotation in the entity called by getReference?
– David Hofmann
Mar 25 '16 at 13:28
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What do querySelectorAll and getElementsBy* methods return?
Do getElementsByClassName (and similar functions like getElementsByTagName and querySelectorAll ) work the same as getElementById or do they return an array of elements?
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Push Notifications in Android Platform
... @Dexter, not all Android devices have Google Play installed by default. Most do have it installed by default, especially devices that are purchased from reputable phone vendors, but devices which just have the Android OS flashed to them may not always have Google Play. (For example, a...
How do I get the resource id of an image if I know its name?
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it means i confused by resources in the code and i use it in non activity class
– Milaaaad
Jan 19 '16 at 7:07
1
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Move to another EditText when Soft Keyboard Next is clicked on Android
...ior of the developer.
Change default behaviour of directional navigation by using following XML attributes:
android:nextFocusDown="@+id/.."
android:nextFocusLeft="@+id/.."
android:nextFocusRight="@+id/.."
android:nextFocusUp="@+id/.."
Besides directional navigation you can use tab n...