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Difference between natural join and inner join
...ith duplicate names, 'anonymous' (unnamed) columns, duplicate rows, nulls, etc. SQL doesn't treat tables as relations because it relies on column ordering etc.
The idea behind NATURAL JOIN in SQL is to make it easier to be more faithful to the relational model. The result of the NATURAL JOIN of two...
Single Line Nested For Loops
...te) set of elements. These include any container, lists, sets, generators, etc.
What is the order in which i and j are assigned to elements in object?
They are assigned in exactly the same order as they are generated from each list, as if they were in a nested for loop (for your first comprehe...
C# Object Pooling Pattern implementation
...d/required lifetime of objects, the real reason that the pool is required, etc. Typically pools are special-purpose - thread pools, connection pools, etc. - because it is easier to optimize one when you know exactly what the resource does and more importantly have control over how that resource is ...
Add missing dates to pandas dataframe
...efore merging two dataframes of different index length where joins, merges etc. almost always leads to errors such as a column full of NaNs.
– user3661992
Sep 7 at 10:24
add a...
Benefits of inline functions in C++?
...iler outputs, but with today's optimized compilers, fast CPUs, huge memory etc. (not like in the 1980< where memory was scarce and everything had to fit in 100KB of memory) what advantages do they really have today?
...
Specifying and saving a figure with exact size in pixels
...the same pixel dimensions as the im array.
Note: the OP specified no axes, etc. which is what this solution does exactly. If one wants to add axes, ticks, etc. my preferred approach is to do that on a separate plot, saving with transparent=True (PNG or PDF) then overlay the latter on the image. This...
What's a good rate limiting algorithm?
...ard_message();
allowance -= 1.0;
There are no datastructures, timers etc. in this solution and it works cleanly :) To see this, 'allowance' grows at speed 5/8 units per seconds at most, i.e. at most five units per eight seconds. Every message that is forwarded deducts one unit, so you can't se...
Why is arr = [] faster than arr = new Array?
...ntext which may contain the "arguments" object, locally defined variables, etc. If we cannot find it in the Activation object, we begin looking up the scope chain until we reach the global scope. If nothing is found, we throw a ReferenceError.
Once we've located the variable declaration, we invoke...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
...nch prediction does work. Taken branches are problematic for instruction-fetch and decode even when they're predicted perfectly. Some CPUs statically predict branches that aren't in their history table, usually with assume not-taken for forward branches. Intel CPUs don't work that way: they don't...
Cross-browser custom styling for file upload button [duplicate]
...ould still work just fine, so could you send me a link of a jsfiddle/jsbin/etc of the code that doesn't work in IE8?
– Joeytje50
Nov 30 '14 at 19:11
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