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How can I build a small operating system on an old desktop computer? [closed]
...stems, and everything else your OS kernel needs to do to get it up to a bootable state. From that point on it's basically a matter of writing device drivers for the hardware you need to support, and offering implementations of the C library functions to make kernel calls for things like opening file...
Paste multiple columns together
...# 3 3 c-f-i
Alternatively we could update data in place using the data.table package (assuming fresh data)
library(data.table)
setDT(data)[, x := Reduce(function(...) paste(..., sep = "-"), .SD[, mget(cols)])]
data[, (cols) := NULL]
data
# a x
# 1: 1 a-d-g
# 2: 2 b-e-h
# 3: 3 c-f-i
Ano...
SQL Server - When to use Clustered vs non-Clustered Index?
...ing: please very carefully pick your clustered index! Every "regular" data table ought to have a clustered index, since having a clustered index does indeed speed up a lot of operations - yes, speed up, even inserts and deletes! But only if you pick a good clustered index.
It's the most replicated ...
Is there a way to make AngularJS load partials in the beginning and not at when needed?
...e the url forexample: $http.get('app/correction/templates/group-correction-table.html', {cache:$templateCache}); and then whenever I want to load the template I have to use this ugly name :( which I don't like, Like this: <td ng-include="'app/correction/templates/group-correction-table.html'">...
Ruby on Rails. How do I use the Active Record .build method in a :belongs to relationship?
...ethod you pass to a string and dissects it and tries to match it with your table's column names.
– bigpotato
Oct 16 '13 at 17:57
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PostgreSQL - Rename database
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The above suggestions make me think it's better to keep table names restricted to just lowercase letters and underscore if possible!
– Aswin Sanakan
Feb 17 at 6:52
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Using Eloquent ORM in Laravel to perform search of database using LIKE
... you can search the column as usual. The syntax is probably something like table.field.
– Anthony
Mar 2 '16 at 21:04
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SQL Server: Query fast, but slow from procedure
...be made to make sense, since the view does have a join clause that says:
(table.column IS NOT NULL)
So there is some NULLs involved.
The explanation is further proved by returning to Query Analizer, and running
SET ANSI_NULLS OFF
.
DECLARE @SessionGUID uniqueidentifier
SET @SessionGUID = '...
Set a default parameter value for a JavaScript function
...
Here is the compatibility table for ES6 kangax.github.io/compat-table/es6/#default_function_parameters Unfortunately this syntax isn't supported yet.
– freemanoid
Jul 9 '15 at 19:03
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Add a common Legend for combined ggplots
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Update 2015-Feb
See Steven's answer below
df1 <- read.table(text="group x y
group1 -0.212201 0.358867
group2 -0.279756 -0.126194
group3 0.186860 -0.203273
group4 0.417117 -0.002592
group1 -0.212201 0.358867
group2 -0.279756 -0.126194
group3 0.186860 -0.203273
group...