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Rails “validates_uniqueness_of” Case Sensitivity

...validates the uniqueness of 'foo' by asking the DB if that name exists yet and the DB says the name doesn't exist yet. Process B does the same thing and gets the same response Process A submits the insert statement for the new record and succeeds If you have a database constraint requiring uniquenes...
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How to check if an object is an array?

...Array.isArray(obj) (Supported by Chrome 5, Firefox 4.0, IE 9, Opera 10.5 and Safari 5) For backward compatibility you can add the following # only implement if no native implementation is available if (typeof Array.isArray === 'undefined') { Array.isArray = function(obj) { return Object.pr...
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Conditionally ignoring tests in JUnit 4

... //test code below. } Not to mention that it is much easier to capture and use the connection from the Database.connect() method this way. share | improve this answer | f...
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Sending email with PHP from an SMTP server

...l through a server that requires SMTP Auth, you really need to specify it, and set the host, username and password (and maybe the port if it is not the default one - 25). For example, I usually use PHPMailer with similar settings to this ones: $mail = new PHPMailer(); // Settings $mail->IsSMTP...
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Is there shorthand for returning a default value if None in Python? [duplicate]

In C#, I can say x ?? "" , which will give me x if x is not null, and the empty string if x is null. I've found it useful for working with databases. ...
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How do I consume the JSON POST data in an Express application

...See this answer which provides some guidance. If you are using valid JSON and are POSTing it with Content-Type: application/json, then you can use the bodyParser middleware to parse the request body and place the result in request.body of your route. var express = require('express') , app = exp...
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Do browsers send “\r\n” or “\n” or does it depend on the browser?

... The HTTP and MIME specs specify that header lines must end with \r\n, but they aren't clear (some would argue that it isn't clear if they are clear) about what to do with the contents of a TEXTAREA. (See, for instance, this thread fro...
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How/when to use ng-click to call a route?

... Routes monitor the $location service and respond to changes in URL (typically through the hash). To "activate" a route, you simply change the URL. The easiest way to do that is with anchor tags. <a href="#/home">Go Home</a> <a href="#/about">G...
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What is process.env.PORT in Node.js?

... In many environments (e.g. Heroku), and as a convention, you can set the environment variable PORT to tell your web server what port to listen on. So process.env.PORT || 3000 means: whatever is in the environment variable PORT, or 3000 if there's nothing there...
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Double Iteration in List Comprehension

...y don't have much meaning to me! Suppose you have a text full of sentences and you want an array of words. # Without list comprehension list_of_words = [] for sentence in text: for word in sentence: list_of_words.append(word) return list_of_words I like to think of list comprehension a...