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MySQL: Fastest way to count number of rows
...mysql side?
If the COUNT(*) is slow, you should run EXPLAIN on the query, and check if indexes are really used, and where should they be added.
The following is not the fastest way, but there is a case, where COUNT(*) doesn't really fit - when you start grouping results, you can run into problem...
Find a value in an array of objects in Javascript [duplicate]
...have an array of unnamed objects, which contain an array of named objects, and I need to get the object where "name" is "string 1". Here is an example array.
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The differences between .build, .create, and .create! and when should they be used?
So I've been seeing people using .build , .create , and .create! within their controllers more and more lately. What's the difference from just using .new and passing the param'd object and then .save ? Are there pros and cons? Does using these other methods offer benefits?
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Is there a way to auto-adjust Excel column widths with pandas.ExcelWriter?
I am being asked to generate some Excel reports. I am currently using pandas quite heavily for my data, so naturally I would like to use the pandas.ExcelWriter method to generate these reports. However the fixed column widths are a problem.
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What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
If I have some integer n, and I want to know the position of the most significant bit (that is, if the least significant bit is on the right, I want to know the position of the furthest left bit that is a 1), what is the quickest/most efficient method of finding out?
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Importance of varchar length in MySQL table
...serted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessary?
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how to calculate binary search complexity
...ula? log2(7)? I did a brute force calculation with every possible outcome, and came to an answer that did not equal log2(7), so what am I doing wrong?
– Perry Monschau
Nov 27 '16 at 17:08
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Simpler way to create dictionary of separate variables?
...er the name. I will could use both your anwser. Or maybe just use my damn hand to type. Some things are just not made to be that automatized...
– e-satis
Mar 31 '10 at 14:08
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How to get RelativeLayout working with merge and include?
...rom using several levels of nested LinearLayouts to one RelativeLayout and have come across a few problems that I haven not been able to find a workaround for...
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Detect if Visual C++ Redistributable for Visual Studio 2012 is installed
... collected this info from a Windows 10 x64 box. I'm just going to go ahead and dump all of these redist versions and the reg keys I search for to detect installation.:
Visual C++ 2005
Microsoft Visual C++ 2005 Redistributable (x64)
Registry Key: HKLM\SOFTWARE\Classes\Installer\Products\1af2a8da7...