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Should MySQL have its timezone set to UTC?
...e server as long as you have the time set right for the current timezone, know the timezone of the datetime columns that you store, and are aware of the issues with daylight savings time.
On the other hand if you have control of the timezones of the servers you work with then you can have everythin...
Difference between volatile and synchronized in Java
...ariables cannot be reordered with each other. The difference is that it is now no longer so easy to reorder normal field accesses around them. Writing to a volatile field has the same memory effect as a monitor release, and reading from a volatile field has the same memory effect as a monitor acquir...
In Clojure 1.3, How to read and write a file
I'd like to know the "recommended" way of reading and writing a file in clojure 1.3 .
6 Answers
...
Python to print out status bar and percentage
...t modification: sys.stdout.write("[%-20s] %d%%" % ('='*int(20*j), 100*j)). Now the only change you need to make is to n=21 before the loop (more likely n=len(iterable)), then enumerate over the iterable object. I recommended this edit but it was rejected; apparently functionality "deviates from the ...
In practice, what are the main uses for the new “yield from” syntax in Python 3.3?
... to a generator.
(If we were talking about TCP, yield from g might mean "now temporarily disconnect my client's socket and reconnect it to this other server socket".)
BTW, if you are not sure what sending data to a generator even means, you need to drop everything and read about coroutines first...
What is the difference between a var and val definition in Scala?
...ge the state of that object. At the root of it, however, there was a var.
Now, immutability is a good thing for many reasons. First, if an object doesn't change internal state, you don't have to worry if some other part of your code is changing it. For example:
x = new B(0)
f(x)
if (x.value.value ...
How can you represent inheritance in a database?
...problems identified for the single table method:
Mandatory attributes can now be enforced with NOT NULL.
Adding a new subtype requires adding a new table instead of adding columns to an existing one.
There is also no risk that an inappropriate attribute is set for a particular subtype, such as th...
How do I set a variable to the output of a command in Bash?
...myDate '2000-01-01'
946681200
myDate "$(ps ho lstart 1)" boottime
myDate now now ; read utm idl </proc/uptime
myBc "$now-$boottime" uptime
printf "%s\n" ${utm%%.*} $uptime
42134906
42134906
ps --tty pts/20 fw
PID TTY STAT TIME COMMAND
29019 pts/20 Ss 0:00 bash
30944 pt...
Exclude folder from search but not from the project list
...
I think this answer is out dated now. Setting > Project Settings > Scopes doesnt seem to exist
– Andrew
Dec 16 '16 at 13:47
3
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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...e']) ? $_POST['value'] : '';
This has become much cleaner as of PHP 7.0, now you can use the null coalesce operator:
// Null coalesce operator - No need to explicitly initialize the variable.
$value = $_POST['value'] ?? '';
Set a custom error handler for E_NOTICE and redirect the messages away f...