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Add a default value to a column through a migration
... states are usually explicit, such as the presence of a column, it's type, etc. The change can be rolled back as it's shown there if and only if there was a valid explicit default previously. Since it's common that defaults are undefined, you might have an issue there.
– Elindo...
How do I count unique values inside a list
... Counter(words).values() is nice. We are assuming the the count is in the order of first appearance of the list of words? I mean, I'm assuming the count will give us the count of a, then b, then c, then d...
– Monica Heddneck
Aug 19 '17 at 1:12
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Why is a “GRANT USAGE” created the first time I grant a user privileges?
... also specify GRANT USAGE at the global level, database level, table level,etc....
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How do you echo a 4-digit Unicode character in Bash?
...translate to \xe2\x98\xa0, because the machine uses the little endian byte order.
– sigalor
May 15 '16 at 18:07
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How to display a confirmation dialog when clicking an link?
... @CiaranG It always starts like this :), then you add this and that, etc. If you manage to embrace separation of concerns, you will feel cleaner if you get rid of most of these inline handlers. They just have nothing to do in your HTML. At least in my opinion, and at least in most cases. There...
Pandas every nth row
...row-selections.
This assumes, of course, that you have an index column of ordered, consecutive, integers starting at 0.
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Web scraping with Python [closed]
...les redirections, gzipped responses, odd encodings, integrated http cache, etc.
Once you are into Scrapy, you can write a spider in less than 5 minutes that download images, creates thumbnails and export the extracted data directly to csv or json.
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What does it mean when MySQL is in the state “Sending data”?
.... It may be the table itself, an index, a temporary table, a sorted output etc.
If you have a 1M records table (without an index) of which you need only one record, MySQL will still output the status as "sending data" while scanning the table, despite the fact it has not sent anything yet.
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SQL Case Sensitive String Compare
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Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity.
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Print in one line dynamically
...roach but instead of spending time calculating out the last output length, etc,
I simply use ANSI code escapes to move back to the beginning of the line and then clear that entire line before printing my current status output.
import sys
class Printer():
"""Print things to stdout on one lin...