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Prevent row names to be written to file when using write.csv
..., "t.csv")
If you need to write big data out, use fwrite() from the data.table package. It's much faster than both write.csv and write_csv
# install.packages('data.table')
library(data.table)
fwrite(t, "t.csv")
Below is a benchmark that Edouard published on his site
microbenchmark(write.csv(d...
Better techniques for trimming leading zeros in SQL Server?
...eading-zero's.
If you plan on reusing it a lot, then place it in an Inline-Table-Valued-Function (ITVF).
Your concerns about performance problems with UDF's is understandable.
However, this problem only applies to All-Scalar-Functions and Multi-Statement-Table-Functions.
Using ITVF's is perfectly fi...
Why use the SQL Server 2008 geography data type?
... of 18 bytes) for a real comparison.
So comparing storage types:
CREATE TABLE dbo.Geo
(
geo geography
)
GO
CREATE TABLE dbo.LatLng
(
lat decimal(15, 12),
lng decimal(15, 12)
)
GO
INSERT dbo.Geo
SELECT geography::Point(12.3456789012345, 12.3456789012345, 4326)
UNION ALL
SELEC...
How to declare variable and use it in the same Oracle SQL script?
...or
DEFINE stupidvar = 'stupidvarcontent';
SELECT stupiddata
FROM stupidtable
WHERE stupidcolumn = '&stupidvar'
upd:
SQL*Plus: Release 10.2.0.1.0 - Production on Wed Aug 25 17:13:26 2010
Copyright (c) 1982, 2005, Oracle. All rights reserved.
SQL> conn od/od@etalon
Connected.
SQL>...
Align two inline-blocks left and right on same line
...
I think one possible solution to this is to use display: table:
.header {
display: table;
width: 100%;
box-sizing: border-box;
}
.header > * {
display: table-cell;
}
.header > *:last-child {
text-align: right;
}
h1 {
font-size: 32px;
}
nav {
vertical-alig...
I need to generate uuid for my rails application. What are the options(gems) I have? [duplicate]
... the column.
Example in Rails 3 migration
execute <<-SQL
CREATE TABLE some_items (id uuid PRIMARY KEY DEFAULT uuid_generate_v1());
SQL
Might be a better way to do this in Rails 4.
share
|
...
what is faster: in_array or isset? [closed]
...
@Fabrizio - Read up on hashing functions and hash tables.
– David Harkness
Nov 20 '12 at 22:54
|
show 5 more commen...
Resize image in the wiki of GitHub using Markdown
...inside the wiki). Additionally, I had to add one or two images inside of a table. The pipe character was giving me grief because of typical table formatting in markdown. Escaping the pipe inside a table cell is still valid: [[ http://url.to/img.png \| height=48px]].
– DanMad
...
Passing an array to a query using a WHERE clause
...FROM galleries WHERE id IN (1); SELECT password FROM users;/*). Change the table & column names to something you have in your database and try that query, check out the results. You'll find a list of passwords as your result, rather than a list of galleries. Depending on how the data is output, ...
How can I remove the search bar and footer added by the jQuery DataTables plugin?
I am using jQuery DataTables .
18 Answers
18
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