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How to list active / open connections in Oracle?
..."Username", s.machine as "Machine", s.schemaname as "Schema name", s.logon_time as "Login time", s.program as "Program", s.osuser as "Os user", s.status as "Status", nvl(s.process, ' ') as "OS Process id"
from v$session s
where nvl(s.username, 'a') not like 'a' and status like 'ACTIVE'
order by 1,2
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Which is the preferred way to concatenate a string in Python?
...ter of taste, the latter one is the most common. Here are timings with the timeit module:
a = a + b:
0.11338996887207031
a += b:
0.11040496826171875
However, those who recommend having lists and appending to them and then joining those lists, do so because appending a string to a list is presumab...
How to validate phone numbers using regex
...
The formatting code is going to be a waste of time if the numbers are allowed to come from outside the US.
– Daniel Earwicker
Jul 21 '09 at 12:13
26
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How do I add the contents of an iterable to a set?
...can test your beliefs quickly before going public:
>\python27\python -mtimeit -s"it=xrange(10000);a=set(xrange(100))" "a.update(it)"
1000 loops, best of 3: 294 usec per loop
>\python27\python -mtimeit -s"it=xrange(10000);a=set(xrange(100))" "for i in it:a.add(i)"
1000 loops, best of 3: 950 u...
source of historical stock data [closed]
...Is to extract historical data, although they are mainly an outfit for real-time feeds. But here there are quite a few options, some brokers even provide historical data downloads via their APIs, so just pick your poison.
BUT usually all of this data is not very clean, once you really start back te...
Is calculating an MD5 hash less CPU intensive than SHA family functions?
...ly limited by disk I/O).
md5sum of a large 4.6GB file took the exact same time than sha1sum of the same file, same goes with many small files (488 in the same directory). I ran the tests a dozen times and they were consitently getting the same results.
--
It would be very interesting to investiga...
How to measure time taken between lines of code in python?
So in Java, we can do How to measure time taken by a function to execute
7 Answers
7
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Difference between core and processor
...ory chunks.
A CPU may have one or more cores to perform tasks at a given time. These tasks are usually software processes and threads that the OS schedules. Note that the OS may have many threads to run, but the CPU can only run X such tasks at a given time, where X = number cores * number of hard...
What's the reason I can't create generic array types in Java?
...
It's because Java's arrays (unlike generics) contain, at runtime, information about its component type. So you must know the component type when you create the array. Since you don't know what T is at runtime, you can't create the array.
...
Strip HTML from strings in Python
...a valid substitution for proper HTML sanitizing. The rule is not hard: Any time you insert a plain-text string into HTML output, you should always HTML escape it (using cgi.escape(s, True)), even if you "know" that it doesn't contain HTML (e.g. because you stripped HTML content). However, this is no...