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How to check if a column exists in a SQL Server table?
I need to add a specific column if it does not exist. I have something like the following, but it always returns false:
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What does the Q_OBJECT macro do? Why do all Qt objects need this macro?
I just started using Qt and noticed that all the example class definitions have the macro Q_OBJECT as the first line. What is the purpose of this preprocessor macro?
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How to read a text-file resource into Java unit test? [duplicate]
I have a unit test that needs to work with XML file located in src/test/resources/abc.xml . What is the easiest way just to get the content of the file into String ?
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How to print (using cout) a number in binary form?
I'm following a college course about operating systems and we're learning how to convert from binary to hexadecimal, decimal to hexadecimal, etc. and today we just learned how signed/unsigned numbers are stored in memory using the two's complement (~number + 1).
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Count, size, length…too many choices in Ruby?
I can't seem to find a definitive answer on this and I want to make sure I understand this to the "n'th level" :-)
6 Answe...
Getting LaTeX into R Plots
I would like to add LaTeX typesetting to elements of plots in R (e.g: the title, axis labels, annotations, etc.) using either the combination of base/lattice or with ggplot2 .
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“Keep Me Logged In” - the best approach
My web application uses sessions to store information about the user once they've logged in, and to maintain that information as they travel from page to page within the app. In this specific application, I'm storing the user_id , first_name and last_name of the person.
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How do you use the “WITH” clause in MySQL?
I am converting all my SQL Server queries to MySQL and my queries that have WITH in them are all failing. Here's an example:
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JavaScript DOM remove element
I'm trying to test if a DOM element exists, and if it does exist delete it, and if it doesn't exist create it.
5 Answers
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How do I check in JavaScript if a value exists at a certain array index?
Will this work for testing whether a value at position index exists or not, or is there a better way:
18 Answers
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