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Rails.env vs RAILS_ENV

...ewise, you can use RAILS_DEFAULT_LOGGER to get the current logger or RAILS_ROOT to get the path to the root folder. Starting from Rails 2.x, Rails introduced the Rails module with some special methods: Rails.root Rails.env Rails.logger This isn't just a cosmetic change. The Rails module offers ...
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Semicolons superfluous at the end of a line in shell scripts?

... on terminal or in shell script. See the below examples: On terminal: [root@server test]# ls;pwd; On shell script: [root@server test]# cat test4.sh echo "Current UserName:" whoami echo -e "\nCurrent Date:";date; [root@server test]# But I am not agree with the comment that & is equi...
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What is the fastest way to compute sin and cos together?

...nd be aware that using this method involves computing a power and a square root, so if performance is important, make sure to verify that this is actually faster than computing the other trig function directly. – Tyler McHenry Apr 21 '10 at 14:11 ...
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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?

I want to create a database which does not exist through JDBC. Unlike MySQL, PostgreSQL does not support create if not exists syntax. What is the best way to accomplish this? ...
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How to export a Vagrant virtual machine to transfer it

... Does the "clean way" account for databases (mySQL, Wordpress) that might be inside the vm? How can that be synced over to the other pc? – kevllar Feb 17 '16 at 4:33 ...
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Is storing a delimited list in a database column really that bad?

...ient table-scan. May have to resort to regular expressions, for example in MySQL: idlist REGEXP '[[:<:]]2[[:>:]]'* Hard to count elements in the list, or do other aggregate queries. Hard to join the values to the lookup table they reference. Hard to fetch the list in sorted order. To solve th...
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Subqueries vs joins

... Here's an example of how subqueries are evaluated in MySQL 6.0. The new optimizer will convert this kind of subqueries into joins. share | improve this answer | ...
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Received fatal alert: handshake_failure through SSLHandshakeException

...certificate trust path between the certificate issued to the server, and a root CA. In most cases, this is because the root CA's certificate is absent in the trust store, leading to the situation where a certificate trust path cannot exist; the certificate is essentially untrusted by the client. Bro...
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How do I design a class in Python?

...ormat but could easily convert to other formats when outputting (Postgres, MySQL, MongoDB). Now let's think through the Database object. What does this hide and store? Well clearly it can't store the full contents of the database, since that is why we have a database! So what is the point? The goal...
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How to change the ROOT application?

...fault application of a Tomcat 6 webserver to a different application than "ROOT" (inside webapps folder). What is the best way to do this? ...