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In MySQL, can I copy one row to insert into the same table?

...an existing row in the table) but I want to do this without having to list all the columns after the "select", because this table has too many columns. ...
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In Python, how do I indicate I'm overriding a method?

... Based on this and fwc:s answer I created a pip installable package https://github.com/mkorpela/overrides From time to time I end up here looking at this question. Mainly this happens after (again) seeing the same bug in our code base: Someone has forgotten some "interface" i...
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How to take the first N items from a generator or list in Python? [duplicate]

...imple syntax: array[start:stop:step] You can omit any parameter. These are all valid: array[start:], array[:stop], array[::step] Slicing a generator import itertools top5 = itertools.islice(my_list, 5) # grab the first five elements You can't slice a generator directly in Python. itertools.i...
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What's the use of ob_start() in php?

...Think of ob_start() as saying "Start remembering everything that would normally be outputted, but don't quite do anything with it yet." For example: ob_start(); echo("Hello there!"); //would normally get printed to the screen/output to browser $output = ob_get_contents(); ob_end_clean(); There a...
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How to rename with prefix/suffix?

...available and you have to rename more than one file, shell scripting can really be short and simple for this. For example, to rename all *.jpg to prefix_*.jpg in the current directory: for filename in *.jpg; do mv "$filename" "prefix_$filename"; done; ...
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CSS styling in Django forms

...ling, if you need an unique identifier its better to use id. Second its usually the template side's responsobilty to do exaclty this, Esspecially if you are going to access this class via frontend methods (js, css). I didn't say your answer is wrong. In my opinion its just bad practice (esspecially ...
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Using PUT method in HTML form

... XHTML 1.x forms only support GET and POST. GET and POST are the only allowed values for the "method" attribute. share | improve this answer | follow | ...
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How to get line count of a large file cheaply in Python?

... You can't get any better than that. After all, any solution will have to read the entire file, figure out how many \n you have, and return that result. Do you have a better way of doing that without reading the entire file? Not sure... The best solution will always ...
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Why does Windows64 use a different calling convention from all other OSes on x86-64?

AMD has an ABI specification that describes the calling convention to use on x86-64. All OSes follow it, except for Windows which has it's own x86-64 calling convention. Why? ...
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What's the difference between using CGFloat and float?

I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference? ...