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How to request a random row in SQL?
...is post: SQL to Select a random row from a database table. It goes through methods for doing this in MySQL, PostgreSQL, Microsoft SQL Server, IBM DB2 and Oracle (the following is copied from that link):
Select a random row with MySQL:
SELECT column FROM table
ORDER BY RAND()
LIMIT 1
Select a ran...
What is the difference between String.Empty and “” (empty string)?
...etween String.Empty and "" , and are they interchangable, or is there some underlying reference or Localization issues around equality that String.Empty will ensure are not a problem?
...
Can I convert a C# string value to an escaped string literal
...er.CreateProvider("CSharp"))
{
provider.GenerateCodeFromExpression(new CodePrimitiveExpression(input), writer, null);
return writer.ToString();
}
}
}
This code:
var input = "\tHello\r\n\tWorld!";
Console.WriteLine(input);
Console.WriteLine(ToLiteral(inp...
How do I escape characters in c# comments?
I realized today that I don't know how to escape characters in comments for C#. I want to document a generic C# class, but I can not write a proper example since I don't know how to escape the < and > characters. Do I have to use &lt; and &gt; ? I don't like if that is the case ...
How to clone an InputStream?
I have a InputStream that I pass to a method to do some processing. I will use the same InputStream in other method, but after the first processing, the InputStream appears be closed inside the method.
...
How does Angular $q.when work?
Can some one explain me how does $q.when work in AngularJS?
I'm trying to analyse how $http work and found this:
1 Answ...
How to select the first element with a specific attribute using XPath
...e:
(/bookstore/book[@location='US'])[1]
This will first get the book elements with the location attribute equal to 'US'. Then it will select the first node from that set. Note the use of parentheses, which are required by some implementations.
Note, this is not the same as /bookstore/book[1][@l...
Python nonlocal statement
What does the Python nonlocal statement do (in Python 3.0 and later)?
9 Answers
9
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Convert string to nullable type (int, double, etc…)
I am attempting to do some data conversion. Unfortunately, much of the data is in strings, where it should be int's or double, etc...
...
Database design for a survey [closed]
...tored in a database. I'm just wondering what would be the best way to implement this in the database, specifically the tables required. The survey contains different types of questions. For example: text fields for comments, multiple choice questions, and possibly questions that could contain more t...