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Is it possible to GROUP BY multiple columns using MySQL?
...garding SUM using with GROUP BY. If GROUP BY only by one column, then SUMs all values of each distinct (different) the column value sqlfiddle.com/#!9/1cbde2/2. If GROUP BY two columns. Then mysql at first checks if for the first column value there are different values in the second column. If yes, t...
How can I get dictionary key as variable directly in Python (not by searching from value)?
...f you want to print key and value, use the following:
for key, value in my_dict.iteritems():
print key, value
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How to solve “Could not establish trust relationship for the SSL/TLS secure channel with authority”
Really thought I had this issue fixed, but it was only disguised before.
17 Answers
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Starting python debugger automatically on error
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You can use traceback.print_exc to print the exceptions traceback. Then use sys.exc_info to extract the traceback and finally call pdb.post_mortem with that traceback
import pdb, traceback, sys
def bombs():
a = []
print a[0]
if __name__ == '...
How To Change DataType of a DataColumn in a DataTable?
... of the column after the DataTable is filled, you can change it after you call FillSchema, but before you call Fill. For example, say the 3rd column is the one you want to convert from double to Int32, you could use:
adapter.FillSchema(table, SchemaType.Source);
table.Columns[2].DataType = typeof (...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenceException and it does that when the first argument on the evaluation stack is a null ...
Rails: confused about syntax for passing locals to partials
...:partial => 'foo', :locals => {blah blah blah}) then it will pass in all of your arguments as a hash and parse them accordingly.
If you pass in a string as your first argument, it assumes the first argument is your partial name, and will pass the remainder as your locals. However, in that s...
Difference between assertEquals and assertSame in phpunit?
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I use both sporadically, but according to the docs:
assertSame
Reports an error identified by $message if the two variables $expected and $actual do not have the same type and value."
And as you can see in the example below the above exc...
Why is HttpClient BaseAddress not working?
...se class of my RestClient, it was almost invisible and got no attention at all, and I never saw the full url in at my breakpoints etc.
– ProfK
Dec 13 '16 at 14:32
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What does #defining WIN32_LEAN_AND_MEAN exclude exactly?
I found the explanation defining WIN32_LEAN_AND_MEAN "reduces the size of the Win32 header files by excluding some of the less frequently used APIs". Somewhere else I read that it speeds up the build process.
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