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Foreign Key to multiple tables
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You have a few options, all varying in "correctness" and ease of use. As always, the right design depends on your needs.
You could simply create two columns in Ticket, OwnedByUserId and OwnedByGroupId, and have nullable Foreign Keys to each table.
You could create M:M referen...
Any reason why scala does not explicitly support dependent types?
There are path dependent types and I think it is possible to express almost all the features of such languages as Epigram or Agda in Scala, but I'm wondering why Scala does not support this more explicitly like it does very nicely in other areas (say, DSLs) ?
Anything I'm missing like "it is not n...
How can I generate Unix timestamps?
...tOS host (SunOS 5.11 joyent_20171026T003127Z), I've both /usr/bin/date +%s and /usr/xpg4/bin/date +%s` working. Combined with the POSIX.2 recommendation, I think this works on all Solaris too.
– Dereckson
Nov 5 '17 at 17:21
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Using awk to remove the Byte-order mark
... So: awk '{if(NR==1)sub(/^\xef\xbb\xbf/,"");print}' INFILE > OUTFILE and make sure INFILE and OUTFILE are different!
– Steve Clay
Feb 12 '10 at 20:30
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JSON to pandas DataFrame
...t elevation data from a google maps API along a path specified by latitude and longitude coordinates as follows:
11 Answers...
What does a type followed by _t (underscore-t) represent?
...th '_t' since it could cause some confusion. As well as size_t, the C89 standard defines wchar_t, off_t, ptrdiff_t, and probably some others I've forgotten. The C99 standard defines a lot of extra types, such as uintptr_t, intmax_t, int8_t, uint_least16_t, uint_fast32_t, and so on. These new type...
What's the difference between “ ” and “ ”?
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One is non-breaking space and the other is a regular space. A non-breaking space means that the line should not be wrapped at that point, just like it wouldn’t be wrapped in the middle of a word.
Furthermore as Svend points out in his comment, non-...
LINQ To Entities does not recognize the method Last. Really?
...mes down to the fact that eventually it has to translate that query to SQL and SQL has a SELECT TOP (in T-SQL) but not a SELECT BOTTOM (no such thing).
There is an easy way around it though, just order descending and then do a First(), which is what you did.
EDIT:
Other providers will possibly hav...
How to dynamically create generic C# object using reflection? [duplicate]
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Check out this article and this simple example. Quick translation of same to your classes ...
var d1 = typeof(Task<>);
Type[] typeArgs = { typeof(Item) };
var makeme = d1.MakeGenericType(typeArgs);
object o = Activator.CreateInstance(makeme...
Python read-only property
I don't know when attribute should be private and if I should use property.
10 Answers
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