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Linq to Entities join vs groupjoin
... it different from a regular inner Join ? Is it commonly used? Is it only for method syntax? What about query syntax? A c# code example would be nice.
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ITunes review URL and iOS 7 (ask user to rate our app) AppStore show a blank page
...ybody knows if the technique used to ask the user to rate our app and open for him the App Store directly on the rating page is still working on iOS 7 ?
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LINQ: Distinct values
...f values of a "larger" type, but only looking at some subset of properties for the distinctness aspect, you probably want DistinctBy as implemented in MoreLINQ in DistinctBy.cs:
public static IEnumerable<TSource> DistinctBy<TSource, TKey>(
this IEnumerable<TSource> source,
...
How to get WordPress post featured image URL
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Check the code below and let me know if it works for you.
<?php if (has_post_thumbnail( $post->ID ) ): ?>
<?php $image = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'single-post-thumbnail' ); ?>
<div id="custom-bg" style="backg...
jQuery: more than one handler for same event
What happens if I bind two event handlers to the same event for the same element?
8 Answers
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How to implement a unique index on two columns in rails
... indexed. So my question is if I just can remove the indexes who were just for one column or if I have to use all three indexes:
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How to convert a Django QuerySet to a list
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You could do this:
import itertools
ids = set(existing_answer.answer.id for existing_answer in existing_question_answers)
answers = itertools.ifilter(lambda x: x.id not in ids, answers)
Read when QuerySets are evaluated and note that it is not good to load the whole result into memory (e.g. via...
Linq code to select one item
...r if the list is empty, use FirstOrDefault which returns the default value for the element type (null for reference types):
var item = Items.FirstOrDefault(i => i.Id == 123);
if (item != null)
{
// found it
}
Single() and SingleOrDefault() can also be used, but if you are reading from a d...
What's the difference between identifying and non-identifying relationships?
...be confusing because it's common practice these days to create a pseudokey for a child table, but not make the foreign key to the parent part of the child's primary key. Formally, the "right" way to do this is to make the foreign key part of the child's primary key. But the logical relationship is...
Remove by _id in MongoDB console
..."_id": ObjectId("4d512b45cc9374271b02ec4f")});
i.e. you don't need a new for the ObjectId.
Also, note that in some drivers/tools, remove() is now deprecated and deleteOne or deleteMany should be used instead.
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