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Display names of all constraints for a table in Oracle SQL
...
You need to query the data dictionary, specifically the USER_CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with ...
How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
How to get the system uptime in Windows? [closed]
...and line utility checks and displays various system statistics such as installation date, installed hotfixes and more.
Open a Command Prompt and type the following command:
systeminfo
You can also narrow down the results to just the line you need:
systeminfo | find "System Boot Time:"
3: By ...
What does f+++++++++ mean in rsync logs?
...rred, if they were not changed in the meantime. But it will start checking all the files again from the beginning to find out, as it is not aware that it had been interrupted.
2 - Each character is a code that can be translated if you read the section for -i, --itemize-changes in man rsync
Decodin...
Reading binary file and looping over each byte
...hile byte != "":
# Do stuff with byte.
byte = f.read(1)
finally:
f.close()
Python 2.5-2.7
with open("myfile", "rb") as f:
byte = f.read(1)
while byte != "":
# Do stuff with byte.
byte = f.read(1)
Note that the with statement is not available in versio...
What is std::promise?
...get it from the associated future.
The asynchronous provider is what initially creates the shared state that a future refers to. std::promise is one type of asynchronous provider, std::packaged_task is another, and the internal detail of std::async is another. Each of those can create a shared sta...
How to base64 encode image in linux bash / shell
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You need to use cat to get the contents of the file named 'DSC_0251.JPG', rather than the filename itself.
test="$(cat DSC_0251.JPG | base64)"
However, base64 can read from the file itself:
test=$( base64 DSC_0251.JPG )
...
Is it possible to use getters/setters in interface definition?
At the moment, TypeScript does not allow use get/set methods(accessors) in interfaces.
For example:
4 Answers
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Find intersection of two nested lists?
... 3 filter returns an iterable instead of list, so you need to wrap filter calls with list():
c3 = [list(filter(lambda x: x in c1, sublist)) for sublist in c2]
Explanation:
The filter part takes each sublist's item and checks to see if it is in the source list c1.
The list comprehension is exec...
UCenter实现各系统通信的原理 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...原理
1、用户登录bbs，通过logging.php文件中，使用函数uc_user_login验证，如果验证成功，将调用函数uc_user_synlogin（位于uc_client下的client.php文件中）， 在这个函数中调用 uc_api_post('user', 'synlogin', array('uid'=>$uid));之后向UC_API.'/index.php'...