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Difference between Fact table and Dimension table?
... as a Star Schema. A primary purpose of star schema is to simplify a complex normalized set of tables and consolidate data (possibly from different systems) into one database structure that can be queried in a very efficient way.
On its simplest form, it contains a fact table (Example: StoreSales) ...
Join/Where with LINQ and Lambda
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I find that if you're familiar with SQL syntax, using the LINQ query syntax is much clearer, more natural, and makes it easier to spot errors:
var id = 1;
var query =
from post in database.Posts
join meta in database.Post_Metas on post.ID equals meta.Post_ID
w...
Convert SQLITE SQL dump file to POSTGRESQL
... column so that INSERTs with NULL ids will be automatically assigned the next available value. PostgreSQL will also not recognize AUTOINCREMENT commands, so these need to be removed.
You'll also want to check for datetime columns in the SQLite schema and change them to timestamp for PostgreSQL. (Tha...
Why are variables “i” and “j” used for counters?
...mathematics: the summation notation traditionally uses i for the first index, j for the second, and so on. Example (from http://en.wikipedia.org/wiki/Summation):
It's also used that way for collections of things, like if you have a bunch of variables x1, x2, ... xn, then an arbitrary one wil...
How to create Android Facebook Key Hash?
...lthough I keep getting the error openssl not recognised as an internal or external command. The problem is even if I can get this to work, what would I do and with what afterwards?
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Unable to Cast from Parent Class to Child Class
...ying to cast from a parent class to a child class but I get an InvalidCastException. The child class only has one property of type int. Does anyone know what I need to do?
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Matplotlib 2 Subplots, 1 Colorbar
...entirely too long researching how to get two subplots to share the same y-axis with a single colorbar shared between the two in Matplotlib.
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Differences between unique_ptr and shared_ptr [duplicate]
Could someone explain differences between shared_ptr and unique_ptr?
4 Answers
4
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Getting all types that implement an interface
...signment compatibility" not whether interface is implemented are not. For example List<string> doesn't implement IEnumerable<object> but this method will return true in .Net 4.0 due to covariance which is wrong indeed. Correct answer is here
– Sriram Sakthivel
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MySQL Error 1093 - Can't specify target table for update in FROM clause
I have a table story_category in my database with corrupt entries. The next query returns the corrupt entries:
16 Answers...