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Add column with constant value to pandas dataframe [duplicate]
...lumn is because df.index and the Index of your right-hand-side object are different. @zach shows the proper way to assign a new column of zeros. In general, pandas tries to do as much alignment of indices as possible. One downside is that when indices are not aligned you get NaN wherever they aren't...
iphone Core Data Unresolved error while saving
...o save
but the problem that the error is not reproducible ( it appears at different times when doing different tasks)
7 Ans...
How to check Oracle database for long running queries
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This is a good one for finding long operations (e.g. full table scans). If it is because of lots of short operations, nothing will show up.
COLUMN percent FORMAT 999.99
SELECT sid, to_char(start_time,'hh24:mi:ss') stime,
message,( sofar/totalwork)* 100 percent
FROM v$session_longops
WHERE so...
Using backticks around field names
...of mine works at a place which has a policy which bans them, I'm wondering if there's anything wrong with using backticks around field names in MySQL.
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Which is the correct C# infinite loop, for (;;) or while (true)? [closed]
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If you want to go old school, goto is still supported in C#:
STARTOVER:
//Do something
goto STARTOVER;
For a truly infinite loop, this is the go-to command. =)
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How to log PostgreSQL queries?
...g at your new information, I'd say there may be a few other settings to verify:
make sure you have turned on the log_destination variable
make sure you turn on the logging_collector
also make sure that the log_directory directory already exists inside of the data directory, and that the postgres u...
Java String - See if a string contains only numbers and not letters
...ication, and it changes from numbers to letters and such. I have a simple if statement to see if it contains letters or numbers but, something isn't quite working correctly. Here is a snippet.
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What does “WARN Could not determine content-length of response body.” mean and how to I get rid of i
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fyi, if the messages bother you, as a workaround you can use thin (add gem 'thin' to your gemfile, start your server using rails server thin). (oops, just noticed that @Scott Lowe already said this above.)
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Secure hash and salt for PHP passwords
...that MD5 is partially unsafe. Taking this into consideration, I'd like to know which mechanism to use for password protection.
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C++, Free-Store vs Heap
...e-store , while malloc/free operations use the heap .
I'd like to know if there is an actual difference, in practice.
Do compilers make a distinction between the two terms? ( Free store and Heap , not new/malloc )
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