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Difference between Fact table and Dimension table?
...se structure that can be queried in a very efficient way.
On its simplest form, it contains a fact table (Example: StoreSales) and a one or more dimension tables. Each Dimension entry has 0,1 or more fact tables associated with it (Example of dimension tables: Geography, Item, Supplier, Customer, T...
MySQL, better to insert NULL or empty string?
I have a form on a website which has a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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getting date format m-d-Y H:i:s.u from milliseconds
I am trying to get a formatted date, including the microseconds from milliseconds.
15 Answers
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Best practices for storing postal addresses in a database (RDBMS)?
...re frustrating than dealing with a website that is oriented around only US-format addresses. It's a little rude at first, but becomes a serious problem when the validation is also over-zealous.
If you are concerned with going global, the only advice I have is to keep things free-form. Different cou...
Algorithm to compare two images
Given two different image files (in whatever format I choose), I need to write a program to predict the chance if one being the illegal copy of another. The author of the copy may do stuff like rotating, making negative, or adding trivial details (as well as changing the dimension of the image).
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C: differences between char pointer and array [duplicate]
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True, but it's a subtle difference. Essentially, the former:
char amessage[] = "now is the time";
Defines an array whose members live in the current scope's stack space, whereas:
char *pmessage = "now is the time";
Defines a pointer that lives in the current scope's stack...
In C#, how to check if a TCP port is available?
...ports. There are lots of good objects available in the System.Net.NetworkInformation namespace.
Use the IPGlobalProperties object to get to an array of TcpConnectionInformation objects, which you can then interrogate about endpoint IP and port.
int port = 456; //<--- This is your value
bool...
How to add text to request body in RestSharp
...nt to insert XML into the body of my RestRequest in its already serialized form (i.e., as a string). Is there an easy way to do this? It appears the .AddBody() function conducts serialization behinds the scenes, so my string is being turned into <String /> .
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Is it a bad practice to use an if-statement without curly braces? [closed]
...amusing ways.
Maintainability-wise, it's always smarter to use the second form.
EDIT: Ned points this out in the comments, but it's worth linking to here, too, I think. This is not just some ivory-tower hypothetical bullshit: https://www.imperialviolet.org/2014/02/22/applebug.html
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What is the scope of variables in JavaScript?
...r (function scope), let (block scope), and const (block scope). Most other forms of identifier declaration have block scope in strict mode.
Overview
Scope is the region of the codebase over which an identifier is valid.
A lexical environment is a mapping between identifier names and the values assoc...