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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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INNER JOIN ON vs WHERE clause
For simplicity, assume all relevant fields are NOT NULL .
11 Answers
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MySQL: multiple tables or one table with many columns?
So this is more of a design question.
8 Answers
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How do I create an Excel (.XLS and .XLSX) file in C# without installing Microsoft Office?
How can I create an Excel spreadsheet with C# without requiring Excel to be installed on the machine that's running the code?
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How do you serve a file for download with AngularJS or Javascript?
I have some text in a hidden textarea. When a button is clicked I would like to have the text offered for download as a .txt file. Is this possible using AngularJS or Javascript?
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What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
What are the different cases when we use these three? Where should I use one and where should I not?
9 Answers
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Custom domain for GitHub project pages
I have a gh-pages branch in one of my http://github.com repos. The GitHub project pages works fine if I go to http://myuser.github.com/myrepo
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How to differ sessions in browser-tabs?
In a web-application implemented in java using JSP and Servlets; if I store information in the user session, this information is shared from all the tabs from the same browser. How to differ sessions in the browser-tabs?
In this example:
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How to count TRUE values in a logical vector
In R, what is the most efficient/idiomatic way to count the number of TRUE values in a logical vector? I can think of two ways:
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Why do I need an IoC container as opposed to straightforward DI code? [closed]
I've been using Dependency Injection (DI) for a while, injecting either in a constructor, property, or method. I've never felt a need to use an Inversion of Control (IoC) container. However, the more I read, the more pressure I feel from the community to use an IoC container.
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