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SQL SELECT speed int vs varchar
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Int comparisons are faster than varchar comparisons, for the simple fact that ints take up much less space than varchars.
This holds true both for unindexed and indexed access. The fastest way to go is an indexed int column.
As I s...
What does Docker add to lxc-tools (the userspace LXC tools)?
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From the Docker FAQ:
Docker is not a replacement for lxc. "lxc" refers to capabilities of the linux kernel (specifically namespaces and control groups) which allow sandboxing processes from one another, and controlling their resource allocations.
On to...
clearing a char array c
...ng the array as a series of chars, then the only way to clear out the data is to touch every entry. memset is probably the most effective way to achieve this.
On the other hand, if you are choosing to view this as a C/C++ null terminated string, setting the first byte to 0 will effectively clear th...
How to have conditional elements and keep DRY with Facebook React's JSX?
How do I optionally include an element in JSX? Here is an example using a banner that should be in the component if it has been passed in. What I want to avoid is having to duplicate HTML tags in the if statement.
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How to debug Lock wait timeout exceeded on MySQL?
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What gives this away is the word transaction. It is evident by the statement that the query was attempting to change at least one row in one or more InnoDB tables.
Since you know the query, all the tables being accessed are candidates fo...
from list of integers, get number closest to a given value
Given a list of integers, I want to find which number is the closest to a number I give in input:
8 Answers
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How to convert a factor to integer\numeric without loss of information?
...ng section of ?factor:
In particular, as.numeric applied to
a factor is meaningless, and may
happen by implicit coercion. To
transform a factor f to
approximately its original numeric
values, as.numeric(levels(f))[f] is
recommended and slightly more
efficient than
as.numeric(as....
Should I use past or present tense in git commit messages? [closed]
...ur changes in imperative mood, e.g. "make xyzzy do frotz"
instead of "[This patch] makes xyzzy do frotz" or "[I] changed xyzzy
to do frotz", as if you are giving orders to the codebase to change
its behavior.
So you'll see a lot of Git commit messages written in that style. If you're working...
Differences between Exception and Error
... butter of exception handling. The Javadoc explains it well:
An Error is a subclass of Throwable that indicates serious problems that a
reasonable application should not try to catch. Most such errors are abnormal
conditions.
Look at a few of the subclasses of Error, taking some of their ...
What is the use of GO in SQL Server Management Studio & Transact SQL?
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It is a batch terminator, you can however change it to whatever you want
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