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What's the use of session.flush() in Hibernate
...) I have class where I am saving object using code id = session.save(obj); and transaction is committed at very next line but obj is not getting saved to DB ,Why? 2) I saved obj using session.save(obj); with commit and while returning I used return obj.getprimaryID(); In this case obj is saved to DB...
append multiple values for one key in a dictionary [duplicate]
I am new to python and I have a list of years and values for each year. What I want to do is check if the year already exists in a dictionary and if it does, append the value to that list of values for the specific key.
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How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
Can anyone explain how to implement one-to-one, one-to-many and many-to-many relationships while designing tables with some examples?
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Client-server synchronization pattern / algorithm?
... should look at how distributed change management works. Look at SVN, CVS and other repositories that manage deltas work.
You have several use cases.
Synchronize changes. Your change-log (or delta history) approach looks good for this. Clients send their deltas to the server; server consolidat...
Sorted collection in Java
...n/should be used for maintaining a sorted list in Java. I have tried Map and Set , but they weren't what I was looking for.
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Writing to an Excel spreadsheet
... to write some data from my program to a spreadsheet. I've searched online and there seem to be many packages available (xlwt, XlsXcessive, openpyxl). Others suggest to write to a .csv file (never used CSV and don't really understand what it is).
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Passing arguments to “make run”
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@Rob: Nmake has never supported ${} for macro expansion, and it appears to be an archaic form now in make. $() is recommended by every online tutorial I've looked at. $() is also more consistent with other tools such as bash.
– John Knoeller
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printf with std::string?
My understanding is that string is a member of the std namespace, so why does the following occur?
7 Answers
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Why are floating point numbers inaccurate?
...t numbers are represented a lot like scientific notation: with an exponent and a mantissa (also called the significand). A very simple number, say 9.2, is actually this fraction:
5179139571476070 * 2 -49
Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is impossibl...
mysql Foreign key constraint is incorrectly formed error
I have two tables, table1 is the parent table with a column ID and table2 with a column IDFromTable1 (not the actual name) when I put a FK on IDFromTable1 to ID in table1 I get the error Foreign key constraint is incorrectly formed error . I would like to delete table 2 record if tab...