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ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type

...'Modified'. Before changing the state, the state is set to 'Detached' but calling Attach() does throw the same error. I'm using EF6. ...
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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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What does `:_*` (colon underscore star) do in Scala?

...tes: MetaData, scope: NamespaceBinding, child: Node*) which is called as new Elem(prefix, label, attributes, scope, child1, child2, ... childN) but here there is only a sequence, not child1, child2, etc. so this allows the result sequence to be used as the input to the constru...
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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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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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Run a Python script from another Python script, passing in arguments [duplicate]

... I believe it's generally preferable to use subprocess.Popen over os.system: docs.python.org/library/subprocess.html#replacing-os-system. – Katriel Sep 23 '10 at 20:15 ...
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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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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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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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Case objects vs Enumerations in Scala

... deal with an Option[Currency] type that would clearly indicate there is really a matching problem and "encourage" the user of the API to sort it out him/herself. To follow up on the other answers here, the main drawbacks of case objects over Enumerations are: Can't iterate over all instances of t...