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Efficient SQL test query or validation query that will work across all (or most) databases

...for idleness. For example, the JDBC pooling library c3p0 has a property called preferredTestQuery , which gets executed on the connection at configured intervals. Similarly, Apache Commons DBCP has validationQuery . ...
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How to perform Callbacks in Objective-C

...newer) option is to use blocks: @interface MyClass: NSObject { void (^_completionHandler)(int someParameter); } - (void) doSomethingWithCompletionHandler:(void(^)(int))handler; @end @implementation MyClass - (void) doSomethingWithCompletionHandler:(void(^)(int))handler { // NOTE: copyin...
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parsing JSONP $http.jsonp() response in angular.js

... UPDATE: since Angular 1.6 You can no longer use the JSON_CALLBACK string as a placeholder for specifying where the callback parameter value should go You must now define the callback like so: $http.jsonp('some/trusted/url', {jsonpCallbackParam: 'callback'}) Change/access/decla...
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Do zombies exist … in .NET?

I was having a discussion with a teammate about locking in .NET. He's a really bright guy with an extensive background in both lower-level and higher-level programming, but his experience with lower level programming far exceeds mine. Anyway, He argued that .NET locking should be avoided on critic...
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Usages of Null / Nothing / Unit in Scala

...wered Apr 23 '13 at 16:40 pagoda_5bpagoda_5b 6,84711 gold badge2323 silver badges3737 bronze badges ...
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What do 'real', 'user' and 'sys' mean in the output of time(1)?

... time; User and Sys refer to CPU time used only by the process. Real is wall clock time - time from start to finish of the call. This is all elapsed time including time slices used by other processes and time the process spends blocked (for example if it is waiting for I/O to complete). User is t...
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How to load db:seed data into test database automatically?

...ore every test or just once at the beginning. You could put it in a setup call or in a test_helper.rb file. share | improve this answer | follow | ...
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How to copy files across computers using SSH and MAC OS X Terminal [closed]

...compression use SCP: scp username@yourserver.com:~/serverpath/public_html ~/Desktop share | improve this answer | follow | ...
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Are there any O(1/n) algorithms?

... This question isn't as stupid as it might seem. At least theoretically, something such as O(1/n) is completely sensible when we take the mathematical definition of the Big O notation: Now you can easily substitute g(x) for 1/x … it's obvious that the above definition still holds for so...
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Running a Python script from PHP

...e if PHP script runs in browser or curl) and/or must be "executable". Also all commands into .py file must have correct privileges: Taken from php manual: Just a quick reminder for those trying to use shell_exec on a unix-type platform and can't seem to get it to work. PHP executes as the w...