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PostgreSQL - fetch the row which has the Max value for a column
...that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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How to use UIScrollView in Storyboard
I have a scroll view with content that is 1000px tall and would like to be able to lay it out for easy design on the storyboard.
I know it can be done programmatically but I really want to be able to see it visually. Every time I put a scroll view on a view controller it won't scroll. Is it possib...
Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
... have read the quote :
data depends on the key [1NF], the whole key [2NF] and nothing but the key [3NF] .
6 Answers
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Float vs Decimal in ActiveRecord
...ation defines floats in binary format. Basically, it stores sign, fraction and exponent to represent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to store fractions and decimals in Float exactly.
That's why there is a Decimal for...
What is the most useful script you've written for everyday life? [closed]
...of each other as an o, two 0 keystrokes within 700 MS of each other as a 0 and ignore the rest; so I could use my laptop before I get around to replacing the keyboard.
Wow; I didn't know this would be so popular :p
As for how - Microsoft exposes a nice little API feature called Hooks.
Using that ...
How do I replace NA values with zeros in an R dataframe?
I have a data frame and some columns have NA values.
21 Answers
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Unbound classpath container in Eclipse
I have checked out a project using Subversive for Eclipse and I am getting the following errors:
13 Answers
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How to upload a file in Django? [closed]
...xample about this. I spent over 2 hours to dig up all the pieces to understand how this works. With that knowledge I implemented a project that makes possible to upload files and show them as list. To download source for the project, visit https://github.com/axelpale/minimal-django-file-upload-exam...
What is /dev/null 2>&1?
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>> /dev/null redirects standard output (stdout) to /dev/null, which discards it.
(The >> seems sort of superfluous, since >> means append while > means truncate and write, and either appending to or writing to /dev/null has the same n...
How to determine if a number is a prime with regex?
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You said you understand this part, but just to emphasize, the String generated has a length equal to the number supplied. So the string has three characters if and only if n == 3.
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The first part of the regex says, "any character, zero or o...