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SQL join: selecting the last records in a one-to-many relationship
Suppose I have a table of customers and a table of purchases. Each purchase belongs to one customer. I want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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In C#, What is a monad?
There is a lot of talk about monads these days. I have read a few articles / blog posts, but I can't go far enough with their examples to fully grasp the concept. The reason is that monads are a functional language concept, and thus the examples are in languages I haven't worked with (since I haven'...
How are POST and GET variables handled in Python?
In PHP you can just use $_POST for POST and $_GET for GET (Query string) variables. What's the equivalent in Python?
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Difference between using bean id and name in Spring configuration file
Is there any difference between using an id attribute and name attribute on a <bean> element in a Spring configuration file?
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How can I use UUIDs in SQLAlchemy?
Is there a way to define a column (primary key) as a UUID in SQLAlchemy if using PostgreSQL (Postgres)?
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Why can Java Collections not directly store Primitives types?
Java collections only store Objects, not primitive types; however we can store the wrapper classes.
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Nullable Foreign Key bad practice?
Let's say you have a table Orders with a foreign key to a Customer Id. Now, suppose you want to add an Order without a Customer Id, (whether that should be possible is another question) you would have to make the foreign key NULL... Is that bad practice or would you rather work with a link table bet...
This Handler class should be static or leaks might occur: IncomingHandler
I'm developing an Android 2.3.3 application with a service. I have this inside that service to communicate with Main activity:
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Using PowerShell to write a file in UTF-8 without the BOM
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$location / switching between html5 and hashbang mode / link rewriting
I was under the impression that Angular would rewrite URLs that appear in href attributes of anchor tags within tempaltes, such that they would work whether in html5 mode or hashbang mode. The documentation for the location service seems to say that HTML Link Rewriting takes care of the hashbang s...