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How to delete large data of table in SQL without log?
...ty the table, you cannot use WHERE clause to limit the rows being deleted and no triggers will be fired.
On the other hand if you are deleting more than 80-90 Percent of the data, say if you have total of 11 Million rows and you want to delete 10 million another way would be to Insert these 1 mill...
Is there auto type inferring in Java?
...whose scope is within the block where they have been defined. Similar to C and C++, but there is no auto or register keyword. However, the Java compiler will not allow the usage of a not-explicitly-initialized local variable and will give a compilation error (unlike C and C++ where the compiler will...
pandas GroupBy columns with NaN (missing) values
...the same placeholder hack).
However, as described in another answer, from pandas 1.1 you have better control over this behavior, NA values are now allowed in the grouper using dropna=False
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How to get the instance id from within an ec2 instance?
... of a more advanced use (retrieve instance ID as well as availability zone and region, etc.):
EC2_INSTANCE_ID="`wget -q -O - http://169.254.169.254/latest/meta-data/instance-id || die \"wget instance-id has failed: $?\"`"
test -n "$EC2_INSTANCE_ID" || die 'cannot obtain instance-id'
EC2_AVAIL_ZONE=...
Count how many records are in a CSV Python?
...r again (to process the rows, say) then you'll need to reset the iterator, and recreate the reader object: file.seek(0) then fileObject = csv.reader(file)
– KevinTydlacka
Jul 12 '18 at 22:05
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Get line number while using grep
I am using grep recursive to search files for a string, and all the matched files and the lines containing that string are print on the terminal. But is it possible to get the line numbers of those lines too??
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How can I calculate an md5 checksum of a directory?
...l files of a particular type ( *.py for example) placed under a directory and all sub-directories.
15 Answers
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What is Robocopy's “restartable” option?
...t very convinced. Can you elaborate please? If a file is copied partially, and then changed in source, will robocopy /z make corrupted file, like xcopy? Why /z and /b are mutually exclusive? [*](# "(per manual: «/ZB :: use restartable mode; if access denied use Backup mode.»")
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What does {0} mean when initializing an object?
... object, what does it mean? I can't find any references to {0} anywhere, and because of the curly braces Google searches are not helpful.
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Getting a list of values from a list of dicts
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Here's another way to do it using map() and lambda functions:
>>> map(lambda d: d['value'], l)
where l is the list.
I see this way "sexiest", but I would do it using the list comprehension.
Update:
In case that 'value' might be missing as a key use:
&...