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Are soft deletes a good idea? [duplicate]
...o when you need to add him back? Please don't say "include IsDeleted in a compound primary key".).
In a design review, I would expect the developer to demonstrate an awareness of the costs and benefits and to present an excellent reason for doing soft deletes in this manner. "Why not do it?" is n...
R script line numbers at error?
If I am running a long R script from the command line (R --slave script.R), how can I get it to give line numbers at errors?
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Difference between a theta join, equijoin and natural join
I'm having trouble understanding relational algebra when it comes to theta joins, equijoins and natural joins. Could someone please help me better understand it? If I use the = sign on a theta join is it exactly the same as just using a natural join?
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How do you get the footer to stay at the bottom of a Web page?
...ix this? You can see my test page here sheltered-escarpment-6887.herokuapp.com
– Syk
Dec 30 '15 at 15:03
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When should I use the Visitor Design Pattern? [closed]
...Dog: public Animal { };
class Cat: public Animal { };
(Suppose it is a complex hierarchy with a well-established interface.)
Now we want to add a new operation to the hierarchy, namely we want each animal to make its sound. As far as the hierarchy is this simple, you can do it with straight pol...
How to import a Python class that is in a directory above?
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Detecting an undefined object property
...s now. This is the worst possible way to do it. I hope passers-by see this comment and decide to check… ahem… other answers.
– Ry-♦
May 14 '14 at 3:05
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Why use Abstract Base Classes in Python?
...a staticly-typed language, that contract would actually be enforced by the compiler. In Python, you can use EAFP or type introspection to confirm that the unknown object meets this expected contract.
But there are also higher-level, semantic promises in the contract.
For example, if there is a __str...
How can I get the current date and time in UTC or GMT in Java?
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java.util.Date has no specific time zone, although its value is most commonly thought of in relation to UTC. What makes you think it's in local time?
To be precise: the value within a java.util.Date is the number of milliseconds since the Unix epoch, which occurred at midnight January 1st 197...