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Storing JSON in database vs. having a new column for each key
...ing user related data in my table - I have 2 columns - uid (primary key) and a meta column which stores other data about the user in JSON format.
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Why does NULL = NULL evaluate to false in SQL server
... in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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WARN Could not determine content-length of response body. Set content-length of the response or set
I just upgraded to rails 3.2.2, and now on rails s, page load, I get all these errors in the log:
3 Answers
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Regular expression to match DNS hostname or IP Address?
Does anyone have a regular expression handy that will match any legal DNS hostname or IP address?
21 Answers
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How can I get a JavaScript stack trace when I throw an exception?
...n simply call: console.trace(); (MDN Reference)
Edit 1 (2013):
A better (and simpler) solution as pointed out in the comments on the original question is to use the stack property of an Error object like so:
function stackTrace() {
var err = new Error();
return err.stack;
}
This will ge...
Correct use of Multimapping in Dapper
...to use the Multimapping feature of dapper to return a list of ProductItems and associated Customers.
6 Answers
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Suppress Scientific Notation in Numpy When Creating Array From Nested List
...otation when printing numpy ndarrays, wrangle text justification, rounding and print options:
What follows is an explanation for what is going on, scroll to bottom for code demos.
Passing parameter suppress=True to function set_printoptions works only for numbers that fit in the default 8 characte...
How to get HTML 5 input type=“date” working in Firefox and/or IE 10
.../modernizr-custom.js"></script>
<!-- polyfiller file to detect and load polyfills -->
<script src="http://cdn.jsdelivr.net/webshim/1.12.4/polyfiller.js"></script>
<script>
webshims.setOptions('waitReady', false);
webshims.setOptions('forms-ext', {types: 'date'});...
What is ANSI format?
...
ANSI encoding is a slightly generic term used to refer to the standard code page on a system, usually Windows. It is more properly referred to as Windows-1252 on Western/U.S. systems. (It can represent certain other Windows code pages on other systems.) This is essentially an extension of...
Return type of '?:' (ternary conditional operator)
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Expressions don't have return types, they have a type and - as it's known in the latest C++ standard - a value category.
A conditional expression can be an lvalue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues a...