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find vs find_by vs where
...is used as a helper when you're searching for information within a column, and it maps to such with naming conventions. For instance, if you have a column named name in your database, you'd use the following syntax:
Model.find_by(name: "Bob")
.where is more of a catch all that lets you use a bit...
How can I export tables to Excel from a webpage [closed]
...s to Excel from a webpage. I want the export to contain all the formatting and colours.
14 Answers
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Can You Get A Users Local LAN IP Address Via JavaScript?
I know the initial reaction to this question is "no" and "it can't be done" and "you shouldn't need it, you are doing something wrong". What I'm trying to do is get the users LAN IP address, and display it on the web page. Why? Because that's what the page I'm working on is all about, showing as muc...
fatal: early EOF fatal: index-pack failed
I have googled and found many solutions but none work for me.
31 Answers
31
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Convert Rows to columns using 'Pivot' in SQL Server
I have read the stuff on MS pivot tables and I am still having problems getting this correct.
8 Answers
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Context switches much slower in new linux kernels
...e intel_idle driver ignores the user's BIOS configuration for the C-states and dances to its own tune. In other words, even if you completely disable all C states in your PC's (or server's) BIOS, this driver will still force them on during periods of brief inactivity, which are almost always happeni...
One Activity and all other Fragments [closed]
I am thinking of implementing one screen with Activity and all other sreens with Fragments and managing all the fragments thru the activity .
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How many GCC optimization levels are there?
...e even more)
-Ofast (optimize very aggressively to the point of breaking standard compliance)
-Og (Optimize debugging experience. -Og enables optimizations that do not interfere with debugging. It should be the
optimization level of choice for the standard edit-compile-debug cycle, offeri...
What is the difference between linear regression and logistic regression?
...ut as probabilities but it's a mistake because the output can be negative, and greater than 1 whereas probability can not. As regression might actually
produce probabilities that could be less than 0, or even bigger than
1, logistic regression was introduced.
Source: http://gerardnico.com/wiki/dat...
C: What is the difference between ++i and i++?
In C, what is the difference between using ++i and i++ , and which should be used in the incrementation block of a for loop?
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