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How to remove constraints from my MySQL table?
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Postgres, MSSQL, and Oracle all have alter table .. drop constraint. MySQL is the odd one out, it seems.
– Jared Beck
Mar 23 '15 at 23:48
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sizeof single struct member in C
... char text[member_size(Parent, text)];
int used;
} Child;
I'm actually a bit surprised that sizeof((type *)0)->member) is even allowed as a constant expression. Cool stuff.
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impr...
What are the advantages of NumPy over regular Python lists?
... Python objects, at least 4 bytes per pointer plus 16 bytes for even the smallest Python object (4 for type pointer, 4 for reference count, 4 for value -- and the memory allocators rounds up to 16). A NumPy array is an array of uniform values -- single-precision numbers takes 4 bytes each, double-pr...
“Code too large” compilation error in Java
...size for code in Java? I wrote a function with more than 10,000 lines. Actually, each line assigns a value to an array variable.
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How can I get the latest JRE / JDK as a zip file rather than EXE or MSI installer? [closed]
... of JDK from Oracle (for example jdk-7u7-windows-x64.exe)
Download and install 7-Zip (or download 7-Zip portable version if you are not administrator)
With 7-Zip extract all the files from jdk-XuXX-windows-x64.exe into the directory C:\JDK
Execute the following commands in cmd.exe:
cd C:\JDK\.rsrc...
How do I localize the jQuery UI Datepicker?
I really need a localized dropdown calendar. An English calendar doesn't exactly communicate excellence on a Norwegian website ;-)
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django unit tests without a db
... doesn't require the db to set up. And while it is fast to setup a db, I really don't need it in some situations.
11 Answer...
How could I use requests in asyncio?
I want to do parallel http request tasks in asyncio , but I find that python-requests would block the event loop of asyncio . I've found aiohttp but it couldn't provide the service of http request using a http proxy.
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What is the difference between Θ(n) and O(n)?
...e of the algorithm as n gets larger is at most proportional to g(n).
Normally, even when people talk about O(g(n)) they actually mean Θ(g(n)) but technically, there is a difference.
More technically:
O(n) represents upper bound. Θ(n) means tight bound.
Ω(n) represents lower bound.
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Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
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