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How do you effectively model inheritance in a database?
...s:
Table-Per-Type (TPT)
Each class has its own table. The base class has all the base class elements in it, and each class which derives from it has its own table, with a primary key which is also a foreign key to the base class table; the derived table's class contains only the different elements...
Edit and Continue: “Changes are not allowed when…”
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I finally got to solve the problem: UNINSTALL Gallio
Gallio seems to have quite some many rough edges and it's better to not use MbUnit 3.0 but use the MbUnit 2.0 framework but use the gallio runner, that you are running without...
Is it possible to get all arguments of a function as single object inside that function?
...t an "Object which has a length property of a non-negative Integer, and usually some indexed properties." From the mozilla link: "It is similar to an Array, but does not have any Array properties except length."
– Luke
Aug 7 '17 at 13:09
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How to split text without spaces into list of words?
...el the distribution of the output. A good first approximation is to assume all words are independently distributed. Then you only need to know the relative frequency of all words. It is reasonable to assume that they follow Zipf's law, that is the word with rank n in the list of words has probabilit...
How to import an excel file in to a MySQL database
...alues (e.g. ',', while using 'as defined in cell properties' separator for all other values. Best to stay away from CSV.
– afk5min
Apr 12 '14 at 15:14
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Returning IEnumerable vs. IQueryable
...ecution.
The difference is that IQueryable<T> is the interface that allows LINQ-to-SQL (LINQ.-to-anything really) to work. So if you further refine your query on an IQueryable<T>, that query will be executed in the database, if possible.
For the IEnumerable<T> case, it will be L...
How can I tell how many objects I've stored in an S3 bucket?
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There is no way, unless you
list them all in batches of 1000 (which can be slow and suck bandwidth - amazon seems to never compress the XML responses), or
log into your account on S3, and go Account - Usage. It seems the billing dept knows exactly how many object...
What is a difference between
...o it guarantees that when it fetches values from the collection, they will all be E or some subclass (i.e. it's compatible). The drainTo method is trying to put values into the collection, so the collection has to have an element type of E or a superclass.
As an example, suppose you have a class h...
Constructing pandas DataFrame from values in variables gives “ValueError: If using all scalar values
...ipulate it to be index=[100], which works. Q: Isn't Index supposed to logically ordered incrementally, why does python allow Index manipulation?
– Sumanth Lazarus
Aug 2 '19 at 6:08
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How to remove duplicate white spaces in string using Java?
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Like this:
yourString = yourString.replaceAll("\\s+", " ");
For example
System.out.println("lorem ipsum dolor \n sit.".replaceAll("\\s+", " "));
outputs
lorem ipsum dolor sit.
What does that \s+ mean?
\s+ is a regular expression. \s matches a space, tab...