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Should each and every table have a primary key?
I'm creating a database table and I don't have a logical primary key assigned to it. So, I'm thinking about leaving it without a primary key, but I'm feeling a bit guilty about it. Should I?
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How can I get my Twitter Bootstrap buttons to right align?
...sert pull-right into the class attribute and let bootstrap arrange the buttons.
For Bootstrap 2.3, see: http://getbootstrap.com/2.3.2/components.html#misc > Helper classes > .pull-right.
For Bootstrap 3, see: https://getbootstrap.com/docs/3.3/css/#helper-classes > Helper classes.
For B...
What's the best practice for primary keys in tables?
When designing tables, I've developed a habit of having one column that is unique and that I make the primary key. This is achieved in three ways depending on requirements:
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Return a value if no rows are found in Microsoft tSQL
Using a Microsoft version of SQL, here's my simple query. If I query a record that doesn't exist then I will get nothing returned. I'd prefer that false (0) is returned in that scenario. Looking for the simplest method to account for no records.
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What is the difference between IQueryable and IEnumerable?
...; has that IEnumerable<T> doesn't are two properties in particular—one that points to a query provider (e.g., a LINQ to SQL provider) and another one pointing to a query expression representing the IQueryable<T> object as a runtime-traversable abstract syntax tree that can be understoo...
How do I round a decimal value to 2 decimal places (for output on a page)
...5 decimal places, and since I'm using it to represent dollars and cents, I only want the output to be 2 decimal places.
17...
Automatically import modules when entering the python or ipython interpreter
...elf typing import numpy as np almost every single time I fire up the python interpreter. How do I set up the python or ipython interpreter so that numpy is automatically imported?
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OpenLayers vs Google Maps? [closed]
I have used Google Maps a couple of times, but what wondering about OpenLayers .
Before starting any kind of coding, here are a couple of questions that come to my mind,
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How to enable or disable an anchor using jQuery?
...fied href, I would suggest using preventDefault():
// jQuery 1.7+
$(function () {
$('a.something').on("click", function (e) {
e.preventDefault();
});
});
// jQuery < 1.7
$(function () {
$('a.something').click(function (e) {
e.preventDefault();
});
// or
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C# - how to determine whether a Type is a number
...example: System.UInt32/UInt16/Double are all numbers. I want to avoid a long switch-case on the Type.FullName .
18 Answe...