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In .NET, which loop runs faster, 'for' or 'foreach'?
...wer in general, but foreach becomes significantly slower than accessing by index. Having said that, I would still almost always prefer foreach to a for loop where it makes the code simpler - because readability is almost always important, whereas micro-optimisation rarely is.
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How to use LINQ to select object with minimum or maximum property value
...re consistent with methods like First() and the approach of the Dictionary indexer. You could easily adapt it if you wanted though.
– Jon Skeet
May 27 '09 at 6:40
8
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Error Code: 1005. Can't create table '…' (errno: 150)
...me.
One of the key field that you are trying to reference does not have an index and/or is not a primary key. If one of the fields in the relationship is not a primary key, you must create an index for that field.
The foreign key name is a duplicate of an already existing key. Check that the name of...
Why does range(start, end) not include end?
...s which equals len(range(0, 10)). Remember that programmers prefer 0-based indexing.
Also, consider the following common code snippet:
for i in range(len(li)):
pass
Could you see that if range() went up to exactly len(li) that this would be problematic? The programmer would need to explicitl...
How can I remove an element from a list, with lodash?
...ly what I was looking for. Removing an element is trivial if you know the index, but what about when you don't know the index?
– random_user_name
Jan 19 '16 at 23:30
3
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Reference - What does this error mean in PHP?
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Notice: Undefined Index
Happens when you try to access an array by a key that does not exist in the array.
A typical example of an Undefined Index notice would be (demo)
$data = array('foo' => '42', 'bar');
echo $data['spinach'];
echo $...
How to Generate unique file names in C#
...upplied. If the original file exists, it incrementally tries to append an index to the filename until it finds one that doesn't exist. It reads the existing filenames into a HashSet to check for collisions so it's pretty quick (a few hundred filenames per second on my machine), it's thread safe to...
SQL Joins Vs SQL Subqueries (Performance)?
...THINGS SQL though, your mileage may vary. The speed will depend a lot on indexes (do you have indexes on both ID columns? That will help a lot...) among other things.
The only REAL way to tell with 100% certainty which is faster is to turn on performance tracking (IO Statistics is especially use...
Deploying just HTML, CSS webpage to Tomcat
...he html file, which you want to be the starting page for your application, index.html
Start tomcat and point your browser to url "http://localhost:8080/MyApp". Your index.html page will pop up in the browser
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Finding last occurrence of substring in string, replacing that
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@AdamMagyar yes, container[a:b] slices from a up to b-1 index of the container. If 'a' is omitted, then it defaults to 0; if 'b' is omitted it defaults to len(container). The plus operator just concatenates. The rfind function as you pointed out returns the index around which the ...