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Update multiple rows in same query using PostgreSQL

... This is wrong... You will update all rows, even if it is not '123' nor '345'. You should use WHERE column_b IN ('123','456')... – MatheusOl Sep 14 '13 at 3:54 ...
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What is a good regular expression to match a URL? [duplicate]

... I changed your expression a bit so it will work in all cases i need, including uri with http:// or www "/([^\s\.]+\.[^\s]{2,}|www\.[^\s]+\.[^\s]{2,})/gi" – Ismael Jan 14 '15 at 11:08 ...
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mongodb: insert if not exists

... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example: key = {'key':'value'} data = {'key2':'value2', 'key3':'value3'}; coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument This replaces your if-find-els...
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In Python, when should I use a function instead of a method?

...sulation which is so dear to OO design. The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...
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How does BLAS get such extreme performance?

...e optimization. This boost significantly exceeds the second boost from parallelism and other hardware optimizations. By the way, most (or even all) of the high performance BLAS implementations are NOT implemented in Fortran. ATLAS is implemented in C. GotoBLAS/OpenBLAS is implemented in C and i...
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How to get the currently logged in user's user id in Django?

...rs = [{user.id: user.get_name()} for user in logged_in_users] # Query all logged in staff users based on id list all_staff_users = CustomUser.objects.filter(is_resident=False, is_active=True, is_superuser=False) logged_out_users = list() # for some reason exclude() would not work co...
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How to print a percentage value in python?

... Is float(1) really more pythonic than 1.? – Tobias Kienzler Jul 17 '13 at 7:58 ...
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Java Reflection: How to get the name of a variable?

...they are in scope. Perhaps a byte-code engineering library like ASM would allow you to inspect this information at runtime. The only reasonable place I can think of for needing this information is in a development tool, and so byte-code engineering is likely to be useful for other purposes too. ...
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Python 2.7: Print to File

... In Python 3.0+, print is a function, which you'd call with print(...). In earlier version, print is a statement, which you'd make with print .... To print to a file in Python earlier than 3.0, you'd do: print >> f, 'what ever %d', i The >> operator directs pr...
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Programmatically get the cache line size?

All platforms welcome, please specify the platform for your answer. 8 Answers 8 ...