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How do you downgrade rubygems?

...ve rubygems 1.3.1 installed but I want to go back to 1.2.0. What's the command to downgrade rubygems? 6 Answers ...
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Canary release strategy vs. Blue/Green

My understanding of a canary release is that it's a partial release to a subset of production nodes with sticky sessions turned on. That way you can control and minimize the number of users/customers that get impacted if you end up releasing a bad bug. ...
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Why are iframes considered dangerous and a security risk?

Why are iframes considered dangerous and a security risk? Can someone describe an example of a case where it can be used maliciously? ...
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Non-static variable cannot be referenced from a static context

... You must understand the difference between a class and an instance of that class. If you see a car on the street, you know immediately that it's a car even if you can't see which model or type. This is because you compare what you see with t...
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Sql Server equivalent of a COUNTIF aggregate function

...Ls were not an issue, though this can be environment dependent. You could handle nulls such as: SELECT SUM(CASE WHEN ISNULL(myColumn,0)=1 THEN 1 ELSE 0 END) FROM AD_CurrentView share | improve thi...
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How to assign colors to categorical variables in ggplot2 that have stable mapping?

...ata frames can become tedious if they are being pulled from separate files and not all factor levels appear in each file. One way to address this is to create a custom manual colour scale as follows: #Some test data dat <- data.frame(x=runif(10),y=runif(10), grp = rep(LETTERS[1:5],each ...
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How to calculate the number of occurrence of a given character in each row of a column of strings?

... Sorry I was unclear. I was actually responding to tim riffe and telling him that his function threw an error with the problem posed. He may have used your redefinition of the problem but he didn't say so. – IRTFM Sep 14 '12 at 20:14 ...
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Transactions in .net

...should be used? What are the pitfalls to look out for etc. All that commit and rollback stuff. I'm just starting a project where I might need to do some transactions while inserting data into the DB. Any responses or links for even basic stuff about transactions are welcome. ...
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Merging without whitespace conflicts

...'ve got a problem where I've got a large commit which changes about a thousand lines of code, removing whitespace from the end of lines and removing spaces before tabs. ...
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Using two CSS classes on one element [duplicate]

...l not matter so you can also reference it in css like so: .first.social {} and it will be the same as .social.first {} – user1467439 Apr 3 '16 at 21:18 ...