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Difference between a user and a schema in Oracle?
...other stuff.
SYS is a schema that includes tons of tables, views, grants, etc etc etc.
SYSTEM is a schema.....
Technically -- A schema is the set of metadata (data dictionary) used by the database,
typically generated using DDL. A schema defines attributes of the database, such as
tables, colum...
Microsecond timing in JavaScript
...volve looping, you cannot gain access to the value of console.timeEnd() in order to add your timer results together. You can, but it get gets nasty because you have to inject the value of your iterating variable, such as i, and set a condition to detect if the loop is done.
Here is an example becau...
Extracting the last n characters from a string in R
...tringr had been remade using stringi as a backend, so should work with NAs etc. now.
– m-dz
Jul 11 '16 at 10:09
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Clicking the back button twice to exit an activity
...urn;
}
else { Toast.makeText(getBaseContext(), "Tap back button in order to exit", Toast.LENGTH_SHORT).show(); }
mBackPressed = System.currentTimeMillis();
}
Back on accepted answer critique; Using a flag to indicate if it was pressed in last TIME_INTERVAL (say 2000) milliseconds an...
Sort NSArray of date strings or objects
...s @selector(compare:) as the parameter. The -[NSDate compare:] method will order dates in ascending order for you. This is simpler than creating an NSSortDescriptor, and much simpler than writing your own comparison function. (NSDate objects know how to compare themselves to each other at least as e...
Are static class variables possible in Python?
...ges (e.g. Java or c++). You should go study the property object, about the order in which Python attributes are returned, the descriptor protocol, and the method resolution order (MRO).
I present a solution to the above 'gotcha' below; however I would suggest - strenuously - that you do not try to...
What is the best practice for dealing with passwords in git repositories?
... share it with a bigger team of even with automatic tools (for deployment, etc)
– blueFast
May 23 '16 at 10:53
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Building a notification system [closed]
...em on the server (how to store notifications, where to store them, how to fetch them etc...).
4 Answers
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What are the main performance differences between varchar and nvarchar SQL Server data types?
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What about index size, memory usage etc? I assume you always use int when you could use tinyint too "just in case"?
– gbn
Jul 9 '10 at 7:02
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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...etching large items from database.
import gc
# Get the events in reverse order
eids = Event.objects.order_by("-id").values_list("id", flat=True)
for index, eid in enumerate(eids):
event = Event.object.get(id=eid)
# do necessary work with event
if index % 100 == 0:
gc.collect()
...