大约有 40,000 项符合查询结果（耗时：0.0927秒） [XML]
Converting unix timestamp string to readable date
...unctions from the time module are thin wrappers around the corresponding C API and therefore they may be less portable than the corresponding datetime methods otherwise you could use them too:
#!/usr/bin/env python
import time
unix_timestamp = int("1284101485")
utc_time = time.gmtime(unix_timesta...
Is it possible to GROUP BY multiple columns using MySQL?
...garding SUM using with GROUP BY. If GROUP BY only by one column, then SUMs all values of each distinct (different) the column value sqlfiddle.com/#!9/1cbde2/2. If GROUP BY two columns. Then mysql at first checks if for the first column value there are different values in the second column. If yes, t...
Setting an int to Infinity in C++
...or 2 147 483 647) if int is 32 bits wide on your implementation.
If you really need infinity, use a floating point number type, like float or double. You can then get infinity with:
double a = std::numeric_limits<double>::infinity();
...
How do I pass the this context to a function?
...
Javascripts .call() and .apply() methods allow you to set the context for a function.
var myfunc = function(){
alert(this.name);
};
var obj_a = {
name: "FOO"
};
var obj_b = {
name: "BAR!!"
};
Now you can call:
myfunc.ca...
Django filter versus get for single object?
...
get() is provided specifically for this case. Use it.
Option 2 is almost precisely how the get() method is actually implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're vio...
Google fonts URL break HTML5 Validation on w3.org
...(%7C):
<link rel="stylesheet" type="text/css" href="http://fonts.googleapis.com/css?family=Open+Sans:400,600,300,800,700,400italic%7CPT+Serif:400,400italic%7CBree+Serif">
share
|
improve thi...
Mysql - How to quit/exit from stored procedure
...e was no error, then use the accepted answer posted by @piotrm. Most typically, however, you will be bailing due to an error condition (especially in a SQL procedure).
As of MySQL v5.5 you can throw an exception. Negating exception handlers, etc. that will achieve the same result, but in a clean...
str performance in python
...; import dis
>>> dis.dis(lambda: str(100000))
8 0 LOAD_GLOBAL 0 (str)
3 LOAD_CONST 1 (100000)
6 CALL_FUNCTION 1
9 RETURN_VALUE
>>> dis.dis(lambda: '%s' % 100000)
9 0 LOAD...
Node.js throws “btoa is not defined” error
...life two years ago. Buffer.from() is the recommended way to use the Buffer API due to security reasons (although that link will clarify alternatives to Buffer.from() that may apply for Node v0.12.2).
– Jamie Birch
Nov 11 '18 at 13:18
...
Create dynamic URLs in Flask with url_for()
...
Refer to the Flask API document for flask.url_for()
Other sample snippets of usage for linking js or css to your template are below.
<script src="{{ url_for('static', filename='jquery.min.js') }}"></script>
<link rel=styleshee...