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How to disable and re-enable console logging in Python?
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CRITICAL was the word I was looking for. Thanks.
– Nishant
Apr 29 '19 at 12:59
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INSERT IF NOT EXISTS ELSE UPDATE?
...lidDate>phonebook2.validDate;
Be warned that at this point the actual word "UPSERT" is not part of the upsert syntax.
The correct syntax is
INSERT INTO ... ON CONFLICT(...) DO UPDATE SET...
and if you are doing INSERT INTO SELECT ... your select needs at least WHERE true to solve parser ambi...
What is a columnar database?
...se is a concept rather a particular architecture/implementation. In other words, there isn't one particular description on how these databases work; indeed, several are build upon traditional, row-oriented, DBMS, simply storing the info in tables with one (or rather often two) columns (and adding t...
What's the difference between RANK() and DENSE_RANK() functions in oracle?
... 8 | 8 | 5 |
+---+------------+------+------------+
In words
ROW_NUMBER() attributes a unique value to each row
RANK() attributes the same row number to the same value, leaving "holes"
DENSE_RANK() attributes the same row number to the same value, leaving no "holes"
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Random record in ActiveRecord
...can (or table scan, in case clustered index is used like InnoDB). In other words, it's O(N) operation but "WHERE id >= #{rand_id} ORDER BY id ASC LIMIT 1" is O(log N), which is much faster.
– kenn
May 6 '11 at 1:02
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Why do python lists have pop() but not push()
...rticular
semantics, write a little class that
uses a lists
In other words, for stacks implemented directly as Python lists, which already supports fast append(), and del list[-1], it makes sense that list.pop() work by default on the last element. Even if other languages do it differently.
I...
Is there a way to change the environment variables of another process in Unix?
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@kilaka: The key word is the second one — No. The rest of the answer is saying that if you have root privileges or are running a debugger, then maybe you can do it, but for all practical purposes, the answer is No.
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I do not want to inherit the child opacity from the parent in CSS
...tually inherited in CSS. It's a post-rendering group transform. In other words, if a <div> has opacity set you render the div and all its kids into a temporary buffer, and then composite that whole buffer into the page with the given opacity setting.
What exactly you want to do here depends...
Functions that return a function
...ts, like any other object. If you find that not helpful, just replace the word "object" with "thing". You can return any object from a function. You can return a true/false value. An integer (1,2,3,4...). You can return a string. You can return a complex object with multiple properties. And y...
Recursion or Iteration?
...ursive function and the benefits of using tail-end recursion. His closing words really summed up some of my key points I think:
"recursive programming gives the programmer a better way of organizing
code in a way that is both maintainable and logically consistent."
https://developer.ibm...