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NumPy array initialization (fill with identical values)
...th certain values, because it explicitly describes what is being achieved (and it can in principle be very efficient since it performs a very specific task).
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How to change a nullable column to not nullable in a Rails migration?
I created a date column in a previous migration and set it to be nullable. Now I want to change it to be not nullable. How do I go about doing this assuming there are null rows in that database? I'm ok with setting those columns to Time.now if they're currently null.
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Best way to do nested case statement logic in SQL Server
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Nice, I just tested to ensure that it short-circuits, and was suprised to find that it does. So if condition1 checked for a divide by zero, it appears that it's safe to do it in condition2. Not sure if this is guaranteed.
– Cade Roux
Feb ...
Logging uncaught exceptions in Python
...d pointed out, sys.excepthook is invoked every time an exception is raised and uncaught. The practical implication of this is that in your code you can override the default behavior of sys.excepthook to do whatever you want (including using logging.exception).
As a straw man example:
>>> i...
Replace whole line containing a string using Sed
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You can use the change command to replace the entire line, and the -i flag to make the changes in-place. For example, using GNU sed:
sed -i '/TEXT_TO_BE_REPLACED/c\This line is removed by the admin.' /tmp/foo
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Rails create or update magic?
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Rails 6
Rails 6 added an upsert and upsert_all methods that deliver this functionality.
Model.upsert(column_name: value)
[upsert] It does not instantiate any models nor does it trigger Active Record callbacks or validations.
Rails 5, 4, and 3
Not ...
How to correctly use “section” tag in HTML5?
I'm trying to build a layout in HTML5 and after reading several different articles I'm just confused. I'm trying to get some input on how it should be used.
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How to extract year and month from date in PostgreSQL without using to_char() function?
... want to select sql:
SELECT "year-month" from table group by "year-month" AND order by date , where
year-month - format for date "1978-01","1923-12".
select to_char of couse work , but not "right" order:
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mysqldump - Export structure only without autoincrement
I have a MySQL database and I am trying to find a way to export its structure only, without the auto increment values. mysqldump --no-data would almost do the job, but it keeps the auto_increment values. Is there any way to do it without using PHPMyAdmin (that I know it can do it)?
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Default height for section header in UITableView
...hmm.. As for me UITableViewAutomaticDimension returns -1 (hardcoded const) and I don't see any sections at all in my UITableView.
– skywinder
Sep 22 '13 at 21:17
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