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What is the proper way to check for existence of variable in an EJS template (using ExpressJS)?
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@Zikes In this case I'm looking specifically for EJS, so it's on the browser page. But, like TJ said, typeof foo == 'undefined' works. I learned that I could also add a simple !!foo if foo has been defined but is null or empty.
– Aashay Desai
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Entity Framework is Too Slow. What are my options? [closed]
...g on your configuration (POCO, Self-Tracking entities) there is a lot room for optimizations. You can debug the SQL commands (which shouldn't differ between debug and release mode) using the ObjectSet<T>.ToTraceString() method. If you encounter a query that requires further optimization you ca...
How to create a protocol with methods that are optional?
...ls defined in the iPhone SDK, such as the UIActionSheetDelegate protocol for example.
5 Answers
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Read data from SqlDataReader
...(rdr.Read())
{
var myString = rdr.GetString(0); //The 0 stands for "the 0'th column", so the first column of the result.
// Do somthing with this rows string, for example to put them in to a list
listDeclaredElsewhere.Add(myString);
}
}
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How can I read a text file in Android?
...ry this :
I assume your text file is on sd card
//Find the directory for the SD Card using the API
//*Don't* hardcode "/sdcard"
File sdcard = Environment.getExternalStorageDirectory();
//Get the text file
File file = new File(sdcard,"file.txt");
//Read text from file
StringBuilder text = new...
Why use multiple columns as primary keys (composite primary key)
...que.
The alternative is to use a generated (non-intelligent) primary key, for example in this case OrderDetailId. But then you would not always see the relationship as easily. Some folks prefer one way; some prefer the other way.
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How do I see active SQL Server connections?
...rprise. I want to see any active SQL Server connections, and the related information of all the connections, like from which IP address, connect to which database or something.
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Add Foreign Key to existing table
I want to add a Foreign Key to a table called "katalog".
13 Answers
13
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What is the difference between Left, Right, Outer and Inner Joins?
...students without lockers and some lockers that have no students assigned.
For the sake of this example, lets say you have 100 students, 70 of which have lockers. You have a total of 50 lockers, 40 of which have at least 1 student and 10 lockers have no student.
INNER JOIN is equivalent to "show me...
Do SVG docs support custom data- attributes?
...lly correct, they omit the fact that SVG provides an alternative mechanism for data-*. SVG allows any attribute and tag to be included, as long as it doesn't conflict with existing ones (in other words: you should use namespaces).
To use this (equivalent) mechanism:
use mydata:id instead of data...