大约有 45,000 项符合查询结果(耗时:0.0537秒) [XML]
MySQL order by before group by
...ou have the following sample data:
CREATE TABLE wp_posts
(`id` int, `title` varchar(6), `post_date` datetime, `post_author` varchar(3))
;
INSERT INTO wp_posts
(`id`, `title`, `post_date`, `post_author`)
VALUES
(1, 'Title1', '2013-01-01 00:00:00', 'Jim'),
(2, 'Title2', '2013-02-01 0...
How do you give iframe 100% height [duplicate]
...
You can do it with CSS:
<iframe style="position: absolute; height: 100%; border: none"></iframe>
Be aware that this will by default place it in the upper-left corner of the page, but I guess that is what you want to achie...
Can You Get A Users Local LAN IP Address Via JavaScript?
I know the initial reaction to this question is "no" and "it can't be done" and "you shouldn't need it, you are doing something wrong". What I'm trying to do is get the users LAN IP address, and display it on the web page. Why? Because that's what the page I'm working on is all about, showing as muc...
Why rename synthesized properties in iOS with leading underscores? [duplicate]
...project in Xcode 4, the boilerplate code adds an underscore character when it synthesizes the ivars in the implementation file as:
...
Should I use != or for not equal in T-SQL?
...unction the same if you’re using SQL Server AKA T-SQL. If you're using it in stored procedures there is no performance reason to use one over the other. It then comes down to personal preference. I prefer to use <> as it is ANSI compliant.
You can find links to the various ANSI standards ...
Sync data between Android App and webserver [closed]
...ice.
Persistent Storage:
This is how your phone actually stores the data it receives from the webserver. One possible method for accomplishing this is writing your own custom ContentProvider backed by a Sqlite database. A decent tutorial for a content provider can be found here: http://thinkandroi...
How can I create directory tree in C++/Linux?
...
With C++17 or later, there's the standard header <filesystem> with
function
std::filesystem::create_directories
which should be used in modern C++ programs.
The C++ standard functions do not have the POSIX-specific expli...
Python nonlocal statement
...
Compare this, without using nonlocal:
x = 0
def outer():
x = 1
def inner():
x = 2
print("inner:", x)
inner()
print("outer:", x)
outer()
print("global:", x)
# inner: 2
# outer: 1
# global: 0
To this, usi...
In Javascript/jQuery what does (e) mean?
...e been learning how to make functions. A lot of functions have cropped up with (e) in brackets. Let me show you what I mean:
...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...e databases implement DISTINCT under the hood).
If one of them is faster, it's going to be DISTINCT. This is because, although the two are the same, a query optimizer would have to catch the fact that your GROUP BY is not taking advantage of any group members, just their keys. DISTINCT makes this ...
