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How to add a primary key to a MySQL table?
...g table. Otherwise it will be put at the end of the table as it is written now, which can be a little confusing when doing simple SELECT * ...
– StefanK
Apr 12 '19 at 6:45
...
Create Generic method constraining T to an Enum
...None -> defaultValue
This one is easier to maintain since it's a well-known language with full Visual Studio IDE support, but you still need a separate project in your solution for it. However, it naturally produces considerably different IL (the code is very different) and it relies on the FSha...
What is JavaScript garbage collection?
...me
into scope and off the scav list when
they go out of scope.
Every now and then the garbage
collector runs. First it puts a
"mark" on every object, variable,
string, etc – all the memory tracked
by the GC. (JScript uses the VARIANT
data structure internally and there
are ple...
How to check if a process id (PID) exists
...s -p $PID > /dev/null
then
echo "$PID is running"
# Do something knowing the pid exists, i.e. the process with $PID is running
fi
The problem with:
kill -0 $PID
is the exit code will be non-zero even if the pid is running and you dont have permission to kill it. For example:
kill -0 1...
Is there a good charting library for iPhone? [closed]
I have a need to render and display charts (bar charts for now, but more types may be needed later) in an iPhone app I'm working on. I've done some looking around and it doesn't look like there are any really good, mature charting libraries for iPhone yet. I've also looked for something written for ...
open read and close a file in 1 line of code
Now I use:
11 Answers
11
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How to set the JDK Netbeans runs on?
...der NB6.7, NB6.9, NB7.0, which used to run on jdk1.6.0_21 and jdk1.6.0_25. Now I've removed those JDKs and only have jdk1.6.0_26 and jdk1.7.0 left, but I still want to keep the older NBs, but now when I run them, I get this message:
...
A weighted version of random.choice
...
Now you got choices method in the random module
– Jitin
Jul 21 at 8:33
add a comment
...
data.table vs dplyr: can one do something well the other can't or does poorly?
...ters. As Grace Hopper would say, Mind your nanoseconds!
3. Syntax
Let's now look at syntax. Hadley commented here:
Data tables are extremely fast but I think their concision makes it harder to learn and code that uses it is harder to read after you have written it ...
I find this remark poi...
Gradient borders
...
WebKit now (and Chrome 12 at least) supports gradients as border image:
-webkit-border-image: -webkit-gradient(linear, left top, left bottom, from(#00abeb), to(#fff), color-stop(0.5, #fff), color-stop(0.5, #66cc00)) 21 30 30 21 rep...