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How to concatenate columns in a Postgres SELECT?
I have two string columns a and b in a table foo .
8 Answers
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How to limit the maximum value of a numeric field in a Django model?
...as various numeric fields available for use in models, e.g. DecimalField and PositiveIntegerField . Although the former can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain ...
What is a simple command line program or script to backup SQL server databases?
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To backup a single database from the command line, use osql or sqlcmd.
"C:\Program Files\Microsoft SQL Server\90\Tools\Binn\osql.exe"
-E -Q "BACKUP DATABASE mydatabase TO DISK='C:\tmp\db.bak' WITH FORMAT"
You'll also want to read the documentation on BACKUP ...
What is Bit Masking?
I am fairly new to C programming, and I encountered bit masking. Can someone explain to me the general concept and function of bit masking? Examples are much appreciated.
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Is 23,148,855,308,184,500 a magic number, or sheer chance?
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Add the cents to the number and you get 2314885530818450000, which in hexadecimal is 2020 2020 2020 1250.
Do you see the pattern? The first six bytes have been overwritten by spaces (hex 20, dec 32).
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Is < faster than
...n two machine instructions:
A test or cmp instruction, which sets EFLAGS
And a Jcc (jump) instruction, depending on the comparison type (and code layout):
jne - Jump if not equal --> ZF = 0
jz - Jump if zero (equal) --> ZF = 1
jg - Jump if greater --> ZF = 0 and SF = OF
(etc...)
Exa...
CruiseControl [.Net] vs TeamCity for continuous integration?
...nsider better, based on practical experience. I'm planning to do some .Net and some Java development, so I would like to have a tool that supports both these platforms.
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How do I find the duplicates in a list and create another list with them?
How can I find the duplicates in a Python list and create another list of the duplicates? The list only contains integers.
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How to write WinForms code that auto-scales to system font and dpi settings?
...b of implementing auto-scaling in .NET 2.0. At least based on our research and testing so far. However, if some of you out there know better, we'd love to hear from you. (Please don't bother arguing we should switch to WPF... that's not an option right now.)
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Should MySQL have its timezone set to UTC?
...urrent timezone, know the timezone of the datetime columns that you store, and are aware of the issues with daylight savings time.
On the other hand if you have control of the timezones of the servers you work with then you can have everything set to UTC internally and never worry about timezones a...