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Best way to test if a row exists in a MySQL table
I'm trying to find out if a row exists in a table. Using MySQL, is it better to do a query like this:
12 Answers
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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
I'm having a little trouble understanding the pass-by-reference properties of data.table . Some operations seem to 'break' the reference, and I'd like to understand exactly what's happening.
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Why is the shovel operator (
I am working through Ruby Koans.
7 Answers
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How can I update the current line in a C# Windows Console App?
When building a Windows Console App in C#, is it possible to write to the console without having to extend a current line or go to a new line? For example, if I want to show a percentage representing how close a process is to completion, I'd just like to update the value on the same line as the cur...
How to check if a string “StartsWith” another string?
How would I write the equivalent of C#'s String.StartsWith in JavaScript?
19 Answers
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UIView bottom border?
To a UIScrollView *toScrollView (which is the width of the screen), I want to add a gray bottom border (exactly like that of the to-field of the compose view of the iPhone's native Messages app).
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How to print color in console using System.out.println?
How can I print color in console? I want to show data in colors when the processor sends data and in different colors when it receives data.
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Replacing NAs with latest non-NA value
In a data.frame (or data.table), I would like to "fill forward" NAs with the closest previous non-NA value. A simple example, using vectors (instead of a data.frame ) is the following:
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Auto-center map with multiple markers in Google Maps API v3
This is what I use to display a map with 3 pins/markers:
7 Answers
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How to strip HTML tags from a string in SQL Server?
I've got data in SQL Server 2005 that contains HTML tags and I'd like to strip all that out, leaving just the text between the tags. Ideally also replacing things like < with < , etc.
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