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What is the difference between a stored procedure and a view?
...g block in a larger query
Can contain several statements, loops, IF ELSE, etc.
Can perform modifications to one or several tables
Can NOT be used as the target of an INSERT, UPDATE or DELETE
statement.
A View:
Does NOT accept parameters
Can be used as building block in a larger query
Can...
Why extend the Android Application class?
...id tools for global state management instead of static vars/singletons and etc.
– Oleksandr Karaberov
Nov 12 '15 at 12:06
...
Cron job every three days
... you want it to run on specific days of the month, like the 1st, 4th, 7th, etc... then you can just have a conditional in your script that checks for the current day of the month.
if (((date('j') - 1) % 3))
exit();
or, as @mario points out, you can use date('k') to get the day of the year inst...
How do I find the location of the executable in C? [duplicate]
...e path, ie, it contains a /, determine the current working directory with getcwd() and then append argv[0] to it.
If argv[0] is a plain word, search $PATH looking for argv[0], and append argv[0] to whatever directory you find it in.
Note that all of these can be circumvented by the process which i...
Deleting all pending tasks in celery / rabbitmq
...ee an option to pick a different named queue.
Here's my process:
$ sudo /etc/init.d/celeryd stop # Wait for analytics task to be last one, Ctrl-C
$ ps -ef | grep analytics # Get the PID of the worker, not the root PID reported by celery
$ sudo kill <PID>
$ sudo /etc/init.d/celeryd stop # ...
Xcode 4.2 debug doesn't symbolicate stack call
...
Nothing I tried would fix this (tried both compilers, both debuggers, etc.)
After upgrading XCode for the iOS 5 update, no stack traces seemed to work.
However, I have found an effective work-around - creating my own exception handler (which is also useful for other reasons). First, create a f...
Replacement for deprecated sizeWithFont: in iOS 7?
... a UILabel (not ALWAYS the case, but often so), to prevent duplicated code/etc, you can also replace [UIFont systemFontOfSize:17.0f] with label.font - helps code maintenance by referencing existing data vs. you typing it multiple times or referencing constants all over the place, etc
...
Java EE 6 @javax.annotation.ManagedBean vs. @javax.inject.Named vs. @javax.faces.ManagedBean
... managed bean is an object that its life cycle (construction, destruction, etc) is managed by a container.
In Java ee we have many containers that manage life cycle of their objects, like JSF container, EJB container, CDI container, Servlet container, etc.
All of these containers work kind of ind...
Argument list too long error for rm, cp, mv commands
...eading NULL-delimited input. And the whole dangerous (broken, exploitable, etc.), is fairly ridiculous. Undoubtedly you should be careful when using xargs, but it is not quite eval/evil.
– Reinstate Monica Please
Jul 25 '14 at 22:37
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Why use apparently meaningless do-while and if-else statements in macros?
...ive in the real world. Unless we can guarantee that all the if statements, etc, in our code use braces, then wrapping macros like this is a simple way of avoiding problems.
– Steve Melnikoff
Nov 20 '13 at 17:16
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