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JPA - Returning an auto generated id after persist()
... Its not working giving zero as a Return after persisting the data into table. either refresh is not working at this case .. What should i do for this. please suggest a way... Thank you
– Vikrant Kashyap
Jun 13 '16 at 6:57
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count the frequency that a value occurs in a dataframe column
... x 1 columns]
See the online docs: http://pandas.pydata.org/pandas-docs/stable/groupby.html
Also value_counts() as @DSM has commented, many ways to skin a cat here
In [38]:
df['a'].value_counts()
Out[38]:
b 3
a 2
s 2
dtype: int64
If you wanted to add frequency back to the original d...
How to get UITableView from UITableViewCell?
I have a UITableViewCell which is linked to an object and I need to tell if the cell is visible. From the research I've done, this means I need to somehow access the UITableView that contains it (from there, there are several ways to check if it's visible). So I'm wondering if UITableViewCell ...
Creating a “logical exclusive or” operator in Java
...me result. Therefore, no need for distinct operators. The simplified truth table for a XOR operator is X ^ !X = 1. You cannot short circuit an input in XOR because you have to determine whether the inputs are different. It is a lot easier to understand if you know the fabrication of the actual XOR g...
What is a correct mime type for docx, pptx etc?
...plication/pkcs8", "plf": "application/vnd.pocketlearn", "pnm": "image/x-portable-anymap", "pbm": "image/x-portable-bitmap", "pcf": "application/x-font-pcf", "pfr": "application/font-tdpfr", "pgn": "application/x-chess-pgn", "pgm": "image/x-portable-graymap", "png": "image/x-png", "ppm": "image/x-por...
How can I get the timezone name in JavaScript?
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@DanielCompton oh I didn't know about this table, thanks for correcting it again.
– CommonSenseCode
Sep 3 '18 at 7:34
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What does SQL clause “GROUP BY 1” mean?
...d name, you may also group by ordinal, or position of the field within the table. 1 corresponds to the first field (regardless of name), 2 is the second, and so on.
This is generally ill-advised if you're grouping on something specific, since the table/view structure may change. Additionally, it ma...
How do I grant myself admin access to a local SQL Server instance?
...s=1,3" %%i in (`sqlcmd -S np:\\.\pipe\SQLLocal\%sqlinstance% -E -Q "create table #foo (bar int); declare @rc int; execute @rc = sp_addsrvrolemember '$(sqllogin)', 'sysadmin'; print 'RETURN_CODE : '+CAST(@rc as char)"`) do if .%%i == .RETURN_CODE set sqlresult=%%j
rem
rem stop the SQL servi...
What version of javac built my jar?
...iszewski' https://stackoverflow.com/a/3313839/1497139 class number version table to create a bash script jarv to show the versions of all class files in a jar file.
usage
usage: ./jarv jarfile
-h|--help: show this usage
Example
jarv $Home/.m2/repository/log4j/log4j/1.2.17/log4j-1.2.17.jar
jav...
Are Exceptions in C++ really slow
...g for the presence of exceptions everywhere, the compiler generates a side table that maps any point that may throw an exception (Program Counter) to the a list of handlers. When an exception is thrown, this list is consulted to pick the right handler (if any) and stack is unwound.
Compared to the ...