大约有 40,000 项符合查询结果（耗时：0.0465秒） [XML]
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...
Best practices for in-app database migration for Sqlite
...
I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...
How to reshape data from long to wide format
...
The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
difference between use and require
... not having to reconcile collisions is a good point, and more generally there's a programming style which says "namespaces are a honking great idea, we should have more of them" (from "The Zen of Python") -- so e.g. that style recommends not using "using namespace foo;" in C++, so that reade...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
...rough for i up to n, doing two things: pressing A once and pressing select all + copy followed by paste j times (actually j-i-1 below; note the trick here: the contents are still in the clipboard, so we can paste it multiple times without copying each time). We only have to consider up to 4 consecut...
Python: split a list based on a condition?
What's the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:
...
Web-scraping JavaScript page with Python
...a web driver fast enough and easy to get the work done.
Once you have installed Phantom JS, make sure the phantomjs binary is available in the current path:
phantomjs --version
# result:
2.1.1
Example
To give an example, I created a sample page with following HTML code. (link):
<!DOCTYPE ht...
CodeIgniter: Create new helper?
...o it.
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
if ( ! function_exists('test_method'))
{
function test_method($var = '')
{
return $var;
}
}
Save this to application/helpers/ . We shall call it "new_helper.php"
The first line exists to ...
Drawing a connecting line between two elements [closed]
...ilding applications and integrations for popular libraries, and is commercially licensed.
share
|
improve this answer
|
follow
|
...
Multiple Updates in MySQL
...has new records then i will end up inserting only the ids and count except all other information. if and only if there is an entry for the id then it should update else it should skip. what shall i do?
– Jayapal Chandran
Aug 30 '10 at 13:30
...