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Unique fields that allow nulls in Django

...com/ticket/9039 The issue here is that the normalized "blank" value for a form CharField is an empty string, not None. So if you leave the field blank, you get an empty string, not NULL, stored in the DB. Empty strings are equal to empty strings for uniqueness checks, under both Django and databas...
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jQuery counting elements by class - what is the best way to implement this?

...me class and then I'm going to use it to be added onto a name for an input form. Basically I'm allowing users to click on a <span> and then by doing so add another one for more of the same type of items. But I can't think of a way to count all of these simply with jQuery/JavaScript. ...
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Send file using POST from a Python script

... "files": { "report.xls": "<censored...binary...data>" }, "form": {}, "url": "http://httpbin.org/post", "args": {}, "headers": { "Content-Length": "3196", "Accept-Encoding": "identity, deflate, compress, gzip", "Accept": "*/*", "User-Agent": "python-requests/0.8...
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Learning Regular Expressions [closed]

...lent \d+) matches any non-negative integer \d{4}-\d{2}-\d{2} matches dates formatted like 2019-01-01 Grouping A quantifier modifies the pattern to its immediate left. You might expect 0abc+0 to match '0abc0', '0abcabc0', and so forth, but the pattern immediately to the left of the plus quantifier...
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Override devise registrations controller

I have added a field to the sign-up form that is based on a different model, see How do I use nested attributes with the devise model for the gory details. This part is working fine. ...
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jQuery access input hidden value

... There's a jQuery selector for that: // Get all form fields that are hidden var hidden_fields = $( this ).find( 'input:hidden' ); // Filter those which have a specific type hidden_fields.attr( 'text' ); Will give you all hidden input fields and filter by those with a sp...
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using href links inside tag

... <select name="forma" onchange="location = this.value;"> <option value="Home.php">Home</option> <option value="Contact.php">Contact</option> <option value="Sitemap.php">Sitemap</option> </select&...
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Javascript regex returning true.. then false.. then true.. etc [duplicate]

I have a strange problem with the validation I am writing on a form. It is a 'Check Username' button next to an input. The input default value is the username for example 'betamax'. When I press 'Check Username' it passes the regex and sends the username to the server. The server behaves as expected...
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Converting Integer to String with comma for thousands

... System.out.println(NumberFormat.getNumberInstance(Locale.US).format(35634646)); Output: 35,634,646 share | improve this answer | ...
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JavaScript function in href vs. onclick

...t will all call the same function but may not have unique ids. I have a webform where the user can add and remove items and I put the onclick in the href of the links within the dynamically created divs so I can get a quicker start on processing the script instead of using something less specific li...