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What are the differences between B trees and B+ trees?
... the pointers in a single page of memory. We want to require only one disk read per leaf access, so we don't want to assign more than a page size of pointers to a leaf. If we fill a leaf with a page size of pointers, and then we want to add another pointer to this leaf, we create two children of thi...
What does it mean when MySQL is in the state “Sending data”?
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This is quite a misleading status. It should be called "reading and filtering data".
This means that MySQL has some data stored on the disk (or in memory) which is yet to be read and sent over. It may be the table itself, an index, a temporary table, a sorted output etc.
If you ...
When is it better to use String.Format vs string concatenation?
...as well.
With C# 6
String interpolation makes a lot of things simpler to read in C# 6. In this case, your second code becomes:
xlsSheet.Write($"C{rowIndex}", null, title);
which is probably the best option, IMO.
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Confused about Service vs Factory
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I like this... When i read the thousand lines of sentence from other blogger.. i only manage to understand factory. But i read this... i understand all 3.
– tsohtan
Dec 4 '15 at 10:24
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Warning message: In `…` : invalid factor level, NA generated
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If you are reading directly from CSV file then do like this.
myDataFrame <- read.csv("path/to/file.csv", header = TRUE, stringsAsFactors = FALSE)
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How to handle AccessViolationException
...by your standard managed code. I won't get into the why's or how's here. Read this article about CSE's in the .NET 4.0 Framework:
http://msdn.microsoft.com/en-us/magazine/dd419661.aspx#id0070035
But there is hope. There are a few ways to get around this:
Recompile as a .NET 3.5 assembly and r...
How should strace be used?
...ster than GDB because it looks up errno codes for you, e.g. -EFAULT (oops, read-only buffer) or -ENOENT (oops, ran from the wrong directory where the relative path didn't work).)
– Peter Cordes
Apr 9 '19 at 6:50
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
...r the cases when an approximation suffices, but speed is required. If you read Intel's documentation, you will also find an instruction sequence (reciprocal square-root approximation followed by a single Newton-Raphson step) that gives nearly full precision (~23 bits of accuracy, if I remember prop...
How to refer to relative paths of resources when working with a code repository
...em using a different path separator in the future and want your code to be ready for it, os.pardir will be more portable. I'd make the case that every programmer, even one who never read any python knows the meaning of "..", while "os.pardir" is a level o f indirection one would have to look up in t...
Measure the time it takes to execute a t-sql query
...r doc on how to do this but couldn't find doc that didn't require hours of reading. Can you recommend a "Profiler for Dummies" link?
– TheMoot
Jul 26 '12 at 18:05
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