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SQLAlchemy: Creating vs. Reusing a Session
...ain. The links it holds to your mapped objects are weak referencing, provided the objects are clean of pending changes, so even in that regard the Session will empty itself out back to a brand new state when your application loses all references to mapped objects. If you leave it with its default...
ExecuteReader requires an open and available Connection. The connection's current state is Connectin
...ADO.NET functionality into a DB-Class(me too 10 years ago). Mostly they decide to use static/shared objects since it seems to be faster than to create a new object for any action.
That is neither a good idea in terms of peformance nor in terms of fail-safety.
Don't poach on the Connection-Pool's t...
Typescript: difference between String and string
...ifferences, which will help with the explanation.
var s1 = new String("Avoid newing things where possible");
var s2 = "A string, in TypeScript of type 'string'";
var s3: string;
String is the JavaScript String type, which you could use to create new strings. Nobody does this as in JavaScript the ...
Using Node.js only vs. using Node.js with Apache/Nginx
... webserver in front of Node.js:
Not having to worry about privileges/setuid for the Node.js process. Only root can bind to port 80 typically. If you let nginx/Apache worry about starting as root, binding to port 80, and then relinquishing its root privileges, it means your Node app doesn't have to...
Why use argparse rather than optparse?
... one-or-more style arguments
producing more informative usage messages
providing a much simpler interface for custom types and actions
More information is also in PEP 389, which is the vehicle by which argparse made it into the standard library.
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How do I delete an exported environment variable?
...tomatically every time you open terminal, try looking through the various hidden files in your home directory for it. Or, to see where it is being set, try "grep -r <X> ~" where <X> is the name of the variable. This may take a while if you have a lot of files in your home directory.
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Global and local variables in R
...
Variables declared inside a function are local to that function. For instance:
foo <- function() {
bar <- 1
}
foo()
bar
gives the following error: Error: object 'bar' not found.
If you want to make bar a global variable, you should d...
How to get equal width of input and select fields
.... These elements are vertically aligned. Unfortunately, I can't get equal width of these elements.
4 Answers
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GitHub: Reopening a merged pull request
...d create a new pull request, copying all the details over and probably providing a link to the original pull request to manually save the history.
Might be a nice feature request for future GitHub.
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Java 7 language features with Android
...wondering if anyone has tried using new Java 7 language features with Android?
I know that Android reads the bytecode that Java spits out and turns it to dex. So I guess my question is can it understand the bytecode of Java 7?
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