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How to determine day of week by passing specific date?
...a.util.Calendar, and java.text.SimpleDateFormat are now legacy, supplanted by the java.time classes built into Java 8 & Java 9. See Tutorial by Oracle.
– Basil Bourque
Nov 3 '17 at 21:25
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Are static class instances unique to a request or a server in ASP.NET?
... application pool is recycled, and therefore everything that is referenced by the static instance, will not be GC'ed. This can lead to memory usage problems.
If you need an instance with the same lifetime as a request, I would suggest to use the HttpContext.Current.Items collection. This is by desi...
What is Normalisation (or Normalization)?
...t each cell should have only one value. We can normalize this problem away by have a separate row per car:
UserId | Car
---------------------
1 | Toyota
2 | Ford
2 | Cadillac
The problem with having several values in one cell is that it is tricky to update, tricky to query against,...
What is the largest Safe UDP Packet Size on the Internet
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It is true that a typical IPv4 header is 20 bytes, and the UDP header is 8 bytes. However it is possible to include IP options which can increase the size of the IP header to as much as 60 bytes. In addition, sometimes it is necessary for intermediate nodes to encaps...
How does Python 2 compare string and int? Why do lists compare as greater than numbers, and tuples g
...plementation detail: Objects of different types except numbers are ordered by their type names; objects of the same types that don’t support proper comparison are ordered by their address.
When you order two strings or two numeric types the ordering is done in the expected way (lexicographic ord...
Django select only rows with duplicate field values
...alues('name')
.annotate(Count('id'))
.order_by()
.filter(id__count__gt=1)
This is as close as you can get with Django. The problem is that this will return a ValuesQuerySet with only name and count. However, you can then use this to construct a regular...
How to declare a structure in a header that is to be used by multiple files in c?
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if this structure is to be used by some other file func.c how to do it?
When a type is used in a file (i.e. func.c file), it must be visible. The very worst way to do it is copy paste it in each source file needed it.
The right way is putting it in an heade...
How to avoid warning when introducing NAs by coercion
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Although this is the preferred response, the answer by jangorecki below seems, to me, more solid.
– Ian
Jul 6 at 15:29
add a comment
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Unexpected value from nativeGetEnabledTags: 0
...round I'm filtering the LogCat output with the following expression on the by Log Message field of the filter:
^(?!.*(nativeGetEnabledTags)).*$
Otherwise it is so spammed it's almost useless.
Following Laksh suggestion, if you want to filter this always without having to always write it on th...
Rails raw SQL example
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@baash05 What do you mean by "in favour of accessing it via the class." - this talks about how to access the table without a model ariond it
– Yo Ludke
Dec 3 '14 at 10:39
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