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MySQL: Transactions vs Locking Tables
...is transferred. And the bank's account, into which they'll happily deposit all the service fees charged on the transaction. Given (as everyone knows these days) that banks are extraordinarily stupid, let's say their system works like this:
$balance = "GET BALANCE FROM your ACCOUNT";
if ($balance &l...
What is the purpose of the reader monad?
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Don't be scared! The reader monad is actually not so complicated, and has real easy-to-use utility.
There are two ways of approaching a monad: we can ask
What does the monad do? What operations is it equipped with? What is it good for?
How is the monad implemen...
SQL Server Script to create a new user
...fluid than I make it seem above. For example, a Login account is automatically created (in most SQL Server installations) for the Windows Administrator account when the database is installed. In most situations, I just use that when I am administering a database (it has all privileges).
However...
How do I make an http request using cookies on Android?
...ookies when I make subsequent requests). It'd be nice to preserve any and all cookies, but really the only one I care about is the session cookie.
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Calculate distance between two latitude-longitude points? (Haversine formula)
...a that the Wikipedia article uses? Is it more efficient and/or more numerically stable?
– musiphil
Dec 20 '12 at 3:47
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A variable modified inside a while loop is not remembered
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@AvinashYadav The problem isn't really related to while loop or for loop; rather the use of subshell i.e., in cmd1 | cmd2, cmd2 is in a subshell. So if a for loop is executed in a subshell, the unexpected/problematic behaviour will be exhibited.
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Multiple github accounts on the same computer?
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All you need to do is configure your SSH setup with multiple SSH keypairs.
This link is easy to follow (Thanks Eric):
http://code.tutsplus.com/tutorials/quick-tip-how-to-work-with-github-and-multiple-accounts--net-22574
Gen...
Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
5 Answers
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Difference between socket and websocket?
...kets are different than websockets . It seems like they're only conceptually similar.
5 Answers
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What does an exclamation mark mean in the Swift language?
...pple have chosen to declare the types as implicitly unwrapped, making the calling code more convenient, but less safe.
Perhaps Apple might comb through their frameworks in the future, removing the uncertainty of implicitly unwrapped ("probably never nil") parameters and replacing them with optional...