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Fastest Way to Find Distance Between Two Lat/Long Points
I currently have just under a million locations in a mysql database all with longitude and latitude information.
15 Answers...
Django queries - id vs pk
...ry key field i.e. you don't need to care whether the primary key field is called id or object_id or whatever.
It also provides more consistency if you have models with different primary key fields.
share
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Case insensitive string compare in LINQ-to-SQL
... accurate when you're trying to do case insensitive equality checks.
Ideally, the best way to do a case-insensitive equality check would be:
String.Equals(row.Name, "test", StringComparison.OrdinalIgnoreCase)
NOTE, HOWEVER that this does not work in this case! Therefore we are stuck with ToUpp...
How to prevent a jQuery Ajax request from caching in Internet Explorer?
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You can disable caching globally using $.ajaxSetup(), for example:
$.ajaxSetup({ cache: false });
This appends a timestamp to the querystring when making the request. To turn cache off for a particular $.ajax() call, set cache: false on it locally, ...
Difference between exit() and sys.exit() in Python
...raising SystemExit. sys.exit does so in sysmodule.c:
static PyObject *
sys_exit(PyObject *self, PyObject *args)
{
PyObject *exit_code = 0;
if (!PyArg_UnpackTuple(args, "exit", 0, 1, &exit_code))
return NULL;
/* Raise SystemExit so callers may catch it or clean up. */
PyE...
error C2664: “std::list::list(const std::allocator &)”: 不能将参数 1...
...转换为“const std::allocator &”错误日志：error C2664: std::list<_Ty>::list(const std::allocator<_Ty> &): 不能将参数 1 从std::vector<_Ty>转换为const std::...错误日志：
error C2664: “std::list<_Ty>::list(const std::allocator<_Ty> &)”: 不能将参数 1 从
“std::vect...
Why does HTML5 form-validation allow emails without a dot?
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I wonder when the last time someone actually sent an email to localhost!
– Matthew Lock
May 19 '17 at 3:14
2
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How do I print the type of a variable in Rust?
...r
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= note: expected type `()`
found type `{float}`
Or call an invalid method:
let mut my_number = 32.90;
my_number.what_is_this();
error[E0599]: no method named `what_is_this` found for type `{float}` in the current scope
--> src/main.rs:3:15
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3 | my_number.what_is_...
How to quickly check if folder is empty (.NET)?
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There is a new feature in Directory and DirectoryInfo in .NET 4 that allows them to return an IEnumerable instead of an array, and start returning results before reading all the directory contents.
What's New in the BCL in .NET 4 Beta 1
Directory.EnumerateFileSystemEntries method overloads
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How to clear the cache in NetBeans
... me absolutely crazy, trying to track down bugs for hours that weren't actually there -- the class with the main method was not being found, and some custom exception classes were not being recognized as implementing Throwable... I just deleted the stupid cache, and now all of it works fine.
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