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DROP IF EXISTS VS DROP?
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Standard SQL syntax is
DROP TABLE table_name;
IF EXISTS is not standard; different platforms might support it with different syntax, or not support it at all. In PostgreSQL, the syntax is
DROP TABLE IF EXISTS table_name;
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How to create your own library for Android development to be used in every program you write?
I am a Delphi programmer and have written, over the years, hundreds of classes and routines which I can use in every Delphi program I write.
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ASP.NET web.config: configSource vs. file attributes
...file in an ASP.NET-application some sections of config, like appSettings and connectionStrings , supports the attributes file and configSource .
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Measure elapsed time in Swift
...Project Euler problems in Swift
As of Swift 3, there is now a version of Grand Central Dispatch that is "swiftified". So the correct answer is probably to use the DispatchTime API.
My function would look something like:
// Swift 3
func evaluateProblem(problemNumber: Int, problemBlock: () -> Int) ...
Why use Ruby's attr_accessor, attr_reader and attr_writer?
Ruby has this handy and convenient way to share instance variables by using keys like
5 Answers
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Android: How to change CheckBox size?
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You just need to set the related drawables and set them in the checkbox:
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="new checkbox"
android:background="@drawable/my_checkbox_background"
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Simple way to encode a string according to a password?
...simple obfuscation that will obscure things from the very casual observer, and you aren't looking to use third party libraries. I'd recommend something like the Vigenere cipher. It is one of the strongest of the simple ancient ciphers.
Vigenère cipher
It's quick and easy to implement. Something l...
Mean per group in a data.frame [duplicate]
I have a data.frame and I need to calculate the mean per group (i.e. per Month , below).
8 Answers
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Best practice to validate null and empty collection in Java
I want to verify whether a collection is empty and null . Could anyone please let me know the best practice.
9 Answers
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How to get a reference to current module's attributes in Python
What I'm trying to do would look like this in the command line:
3 Answers
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