大约有 47,000 项符合查询结果（耗时：0.0456秒） [XML]
Efficient SQL test query or validation query that will work across all (or most) databases
...g_table WHERE 1=0
or
SELECT 1 FROM INFORMATION_SCHEMA.SYSTEM_USERS
or
CALL NOW()
HSQLDB (tested with version 1.8.0.10)
Note: I tried using a WHERE 1=0 clause on the second query, but it didn't work as a value for Apache Commons DBCP's validationQuery, since the query doesn't return any rows
VAL...
How to configure XAMPP to send mail from localhost?
...ail-id@gmail.com
sendmail_path = "\"C:\xampp\sendmail\sendmail.exe\" -t"
Now Open C:\xampp\sendmail\sendmail.ini. Replace all the existing code in sendmail.ini with following code
[sendmail]
smtp_server=smtp.gmail.com
smtp_port=587
error_logfile=error.log
debug_logfile=debug.log
auth_username=my...
Why doesn't ruby support method overloading?
...hod(a, b = true); end; # second argument has a default value
method(10)
# Now the method call can match the first one as well as the second one,
# so here is the problem.
So ruby needs to maintain one method in the method look up chain with a unique name.
...
Editing screenshots in iTunes Connect after iOS app was approved
...
Apple support now got back with the (somehow not too satisfactory) answer:
If your app is currently for sale on
the App Store, you will need to submit
an update in order to change your app
screenshots.
If you have any furthe...
JavaScript ternary operator example with functions
...unction() ? imlost() : whathappuh() : lostinsyntax() : thisisprobablybrokennow() ? //I'm lost in my own (awful) example by now.
//Not complete... or for average humans to read.
if(this != that) //Ternary would be done by now
{
x = this;
}
else
}
x = this + 2;
}
A really basic rule of thu...
How to explain callbacks in plain english? How are they different from calling one function from ano
...sider how programmers normally write to a file:
fileObject = open(file)
# now that we have WAITED for the file to open, we can write to it
fileObject.write("We are writing to the file.")
# now we can continue doing the other, totally unrelated things our program does
Here, we WAIT for the file to...
arrow operator (->) in function heading
...ifier ( argument-declarations... ) -> return_type
They are equivalent. Now when they are equivalent, why do you ever want to use the latter? Well, C++11 introduced this cool decltype thing that lets you describe type of an expression. So you might want to derive the return type from the argument...
How to write LaTeX in IPython Notebook?
...doing, found a better solution with some more searching, IPython notebooks now have a %%latex magic that makes the whole cell Latex without the $$ wrapper for each line.
Refer notebook tour for Rich Display System
share
...
Why are Subjects not recommended in .NET Reactive Extensions?
...ppropriate FromEvent method and we are done. To the Pub!
For option 2, we now need to consider how we poll this and how to do this effciently. Also when we get the value, how do we publish it?
I would imagine that you would want a dedicated thread for polling. You wouldn't want some other coder ha...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
...
There's a dynamic programming solution. We start off knowing 0 keys can make us 0 A's. Then we iterate through 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 s...