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Foreign key constraint may cause cycles or multiple cascade paths?

...f cascade paths and, rather than trying to work out whether any cycles actually exist, it assumes the worst and refuses to create the referential actions (CASCADE): you can and should still create the constraints without the referential actions. If you can't alter your design (or doing so would comp...
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How do I remove all specific characters at the end of a string in PHP?

... using rtrim replaces all "." at the end, not just the last character $string = "something here.."; echo preg_replace("/\.$/","",$string); share | ...
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How do I change the formatting of numbers on an axis with ggplot?

I'm using R and ggplot to draw a scatterplot of some data, all is fine except that the numbers on the y-axis are coming out with computer style exponent formatting, i.e. 4e+05, 5e+05, etc. This is obviously unacceptable, so I want to get it to display them as 500,000, 400,000, and so on. Getting a p...
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Convert Long into Integer

...yslov the question was about Long values, not about null values. And personally I believe in rejecting null up front rather than using null in -> null out and thereby transporting null through my application. So one could also argue this is the worst answer :-) – Sean Patric...
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Why does sudo change the PATH?

... Yeah, but it's totally counterintuitive. It probably fools the good guys more than the bad guys. – Brian Armstrong Jun 20 '09 at 2:24 ...
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What is console.log?

... Places you can view the console! Just to have them all in one answer. Firefox http://getfirebug.com/ (you can also now use Firefox's built in developer tools Ctrl+Shift+J (Tools > Web Developer > Error Console), but Firebug is much better; use Firebug) Safari and Ch...
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Converting strings to floats in a DataFrame

...newer version of pandas (0.17 and up), you can use to_numeric function. It allows you to convert the whole dataframe or just individual columns. It also gives you an ability to select how to treat stuff that can't be converted to numeric values: import pandas as pd s = pd.Series(['1.0', '2', -3]) p...
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When to use EntityManager.find() vs EntityManager.getReference() with JPA

... I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
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How to convert JSON string to array

...d keys). That's what the documentation says and that's what my PHP 5.2 installation returns. Are you using a function other than the official, built-in json_decode()? What does var_dump(json_decode($str, true)); return? – RickN Sep 22 '11 at 15:34 ...
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Scatterplot with marginal histograms in ggplot2

...m the same distribution though, so the marginal histograms should theoretically match the scatter plot. – oeo4b Dec 17 '11 at 17:03 8 ...