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Surrogate vs. natural/business keys [closed]
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Both. Have your cake and eat it.
Remember there is nothing special about a primary key, except that it is labelled as such. It is nothing more than a NOT NULL UNIQUE constraint, and a table can have more than one.
If you use a surrogate key, y...
Overriding superclass property with different type in Swift
...properties. Instead you can create an extra variable in the subclass that handles the new class type:
class Chassis {}
class RacingChassis : Chassis {}
class Car {
var chassis = Chassis()
}
class RaceCar: Car {
var racingChassis = RacingChassis()
override var chassis: Chassis {
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How can I change my default database in SQL Server without using MS SQL Server Management Studio?
...r Management Studio by using the 'options' button in the connection dialog and selecting 'master' as the database to connect to. However, whenever I try to do anything in object explorer, it tries to connect using my default database and fails.
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Difference between Dictionary and Hashtable [duplicate]
What is the difference between Dictionary and Hashtable. How to decide which one to use?
7 Answers
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Static table view outside UITableViewController
After the new Xcode update, my app doesn't validate and shows this error:
4 Answers
4
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html5 - canvas element - Multiple layers
...ver, you could layer multiple <canvas> elements on top of each other and accomplish something similar.
<div style="position: relative;">
<canvas id="layer1" width="100" height="100"
style="position: absolute; left: 0; top: 0; z-index: 0;"></canvas>
<canvas id="layer...
SQL update trigger only when column is modified
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You have two way for your question :
1- Use Update Command in your Trigger.
ALTER TRIGGER [dbo].[tr_SCHEDULE_Modified]
ON [dbo].[SCHEDULE]
AFTER UPDATE
AS BEGIN
SET NOCOUNT ON;
IF UPDATE (QtyToRepair)
BEGIN
UPDATE SCHEDULE
SET modified = GETDA...
Attempt to present UIViewController on UIViewController whose view is not in the window hierarchy
Just started using Xcode 4.5 and I got this error in the console:
33 Answers
33
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How do you display code snippets in MS Word preserving format and syntax highlighting?
... a way to display code in Microsoft Word documents that preserves coloring and formatting? Preferably, the method would also be unobtrusive and easy to update.
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Format decimal for percentage values?
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Looking at here big difference is like US and France type. If above varies by culture, is there a culture-independent P formatting?
– bonCodigo
May 18 '14 at 1:36
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