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How to drop columns using Rails migration
What's the syntax for dropping a database table column through a Rails migration?
20 Answers
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How to increase font size in a plot in R?
I am confused. What is the right way to increase font size of text in the title, labels and other places of a plot?
7 Answ...
Using the star sign in grep
I am trying to search for the substring "abc" in a specific file in linux/bash
10 Answers
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What does enumerate() mean?
What does for row_number, row in enumerate(cursor): do in Python?
5 Answers
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Matching a space in regex
I need to match a space character in a PHP regular expression. Anyone got any ideas?
9 Answers
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Is there a way to access the “previous row” value in a SELECT statement?
I need to calculate the difference of a column between two lines of a table. Is there any way I can do this directly in SQL? I'm using Microsoft SQL Server 2008.
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How do I rename a column in a database table using SQL?
If I wish to simply rename a column (not change its type or constraints, just its name) in an SQL database using SQL, how do I do that? Or is it not possible?
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Function to clear the console in R and RStudio
I am wondering if there is a function to clear the console in R and, in particular, RStudio I am looking for a function that I can type into the console, and not a keyboard shortcut.
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How to capitalize the first letter in a String in Ruby
The upcase method capitalizes the entire string, but I need to capitalize only the first letter.
8 Answers
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Recommended way to save uploaded files in a servlet application
I read here that one should not save the file in the server anyway as it is not portable, transactional and requires external parameters. However, given that I need a tmp solution for tomcat (7) and that I have (relative) control over the server machine I want to know :
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