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Are Javascript arrays sparse?
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Yes, they are. They are actually hash tables internally, so you can use not only large integers but also strings, floats, or other objects. All keys get converted to strings via toString() before being added to the hash. You can confirm this with some test code:
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select and update database record with a single queryset
...ew value based on the old field value that is do something like:
update my_table set field_1 = field_1 + 1 where pk_field = some_value
use query expressions:
MyModel.objects.filter(pk=some_value).update(field1=F('field1') + 1)
This will execute update atomically that is using one update request to...
Why does Eclipse Java Package Explorer show question mark on some classes?
...s are added to the object icons provided by Eclipse. For example, here's a table of icons for the Java development environment.
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UTF-8 all the way through
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Data Storage:
Specify the utf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly use utf8mb4 encoding if a utf8mb4_* collation is specified (without ...
In Ruby on Rails, what's the difference between DateTime, Timestamp, Time and Date?
...ql/#:~:text=DATETIME%20vs%20TIMESTAMP%3A,DATETIME%20is%20constant.
Also...
table with different column "date" types and corresponding rails migration types depending on the database
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How to Publish Web with msbuild?
...Version parameter depend on your version of Visual Studio. Wikipedia has a table of Visual Studio releases and their versions.
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Getting key with maximum value in dictionary?
...th item>
Returned values will be compared.
Dict
Python dict is a hash table. A key of dict is a hash of an object declared as a key. Due to performance reasons iteration though a dict implemented as iteration through it's keys.
Therefore we can use it to rid operation of obtaining a keys list.
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How does Stack Overflow generate its SEO-friendly URLs?
... from full (profile) URL), and then ignore any characters outside the acceptable ranges. This works most of the time...
... For when it doesn’t I’ve also had to add a lookup table. As mentioned above, some characters don’t map to a low ASCII value when normalised. Rather than drop these I’ve...
Naming convention - underscore in C++ and C# variables
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Except for teams that want their properties to be immutable.
– ChaosPandion
Jun 28 '10 at 22:34
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Why does Math.Round(2.5) return 2 instead of 3?
...5,MidpointRounding.AwayFromZero)" becoming 3).
The following diagram and table may help:
-3 -2 -1 0 1 2 3
+--|------+---------+----|----+--|------+----|----+-------|-+
a b c d e
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