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T-SQL CASE Clause: How to specify WHEN NULL
...this is what ANSI defines for null, and can be verified even in SQL Server by using case statements etc.)
SELECT NULL = NULL -- Results in NULL
SELECT NULL <> NULL -- Results in NULL
So there is no true/false answer to the question, instead the answer is also null.
This has many implicati...
Android AlertDialog Single Button
...
Couldn't that just be done by only using a positive button?
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Look at this dialog!")
.setCancelable(false)
.setPositiveButton("OK", new DialogInterface.OnClic...
Static and Sealed class differences
...c
class using the new keyword. Static classes are loaded automatically
by the .NET Framework common language runtime (CLR) when the program
or namespace containing the class is loaded.
Sealed Class
A sealed class cannot be used as a base class. Sealed classes are
primarily used to prev...
Printing tuple with string formatting in Python
...nswer.
Since the general tuple printing method is already shown correctly by Antimony, this is an addition for printing each element in a tuple separately, as Fong Kah Chun has shown correctly with the %s syntax.
Interestingly it has been only mentioned in a comment, but using an asterisk operator...
How to check if a URL is valid
...
Use the URI module distributed with Ruby:
require 'uri'
if url =~ URI::regexp
# Correct URL
end
Like Alexander Günther said in the comments, it checks if a string contains a URL.
To check if the string is a URL, use:
url =~ /\A#{URI::regexp}\z/
If yo...
How to determine an object's class?
...to find the runtime class of the object in picture. If Parent1 is extended by Child1 and Child2, try the following code Child1 child1 = new Child1(); Parent1 parentChild = new Child2(); Child2 child2 = new Child2(); (child1 instanceof Parent1); (child1 instanceof Child1); (parentChild instanceof Ch...
PreparedStatement with list of parameters in a IN clause [duplicate]
...What you can do is dynamically build the select string (the 'IN (?)' part) by a simple for loop as soon as you know how many values you need to put inside the IN clause. You can then instantiate the PreparedStatement.
share
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A more useful statusline in vim? [closed]
...
c is actually the byte count, even if it is sometimes called column count even in vim help. You can use v to get what is usually meant by column number.
– Ludwig Weinzierl
Jan 3 '12 at 17:26
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When would you call java's thread.run() instead of thread.start()?
...question is not asking for the difference, but asking about use cases whereby we will call thread.run() instead of thread.start().
– Pacerier
Sep 26 '14 at 2:19
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Ruby: How to post a file via HTTP as multipart/form-data?
...o an HTTP POST that looks like an HMTL form posted from a browser. Specifically, post some text fields and a file field.
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