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Only read selected columns
...from the data.table-package:
You can specify the desired columns with the select parameter from fread from the data.table package. You can specify the columns with a vector of column names or column numbers.
For the example dataset:
library(data.table)
dat <- fread("data.txt", select = c("Year...
Better techniques for trimming leading zeros in SQL Server?
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Why don't you just cast the value to INTEGER and then back to VARCHAR?
SELECT CAST(CAST('000000000' AS INTEGER) AS VARCHAR)
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0
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How to use a class from one C# project with another C# project
...Explorer' tree, expand the P2 project and then right-click the project and select 'Add Reference' from the menu.
On the 'Add Reference' dialog, select the 'Projects' tab and select your P1 project.
If you are using namespaces then you will need to import the namespaces for your P1 types by adding ...
Checking oracle sid and database name
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I presume SELECT user FROM dual; should give you the current user
and SELECT sys_context('userenv','instance_name') FROM dual; the name of the instance
I believe you can get SID as SELECT sys_context('USERENV', 'SID') FROM DUAL;
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How to insert text at beginning of a multi-line selection in vi/Vim
In Vim , how do I insert characters at the beginning of each line in a selection?
13 Answers
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How can I make an entire HTML form “readonly”?
...e="text" name="something" placeholder="enter some text" />
<select>
<option value="0" disabled="disabled" selected="selected">select somethihng</option>
<option value="1">woot</option>
<option value="2">is</opt...
How to use Oracle ORDER BY and ROWNUM correctly?
...n Oracle.
If you want a version that works in both servers, you can use:
select ril.*
from (select ril.*, row_number() over (order by t_stamp desc) as seqnum
from raceway_input_labo ril
) ril
where seqnum = 1
The outer * will return "1" in the last column. You would need to list the ...
In jQuery, how do I select an element by its name attribute?
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Good point. Although it's still not "How to get selected radiobutton value using its name in jQuery?". It's "How to get selected radiobutton value when clicking on it using jQuery?". A small difference, but one that baffled me for a bit.
– gargantuan
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How do you count the number of occurrences of a certain substring in a SQL varchar?
...mparing the lengths
Declare @string varchar(1000)
Set @string = 'a,b,c,d'
select len(@string) - len(replace(@string, ',', ''))
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System.Net.Http: missing from namespace? (using .net 4.5)
... Add Reference dialog right-click on your project in Solution Explorer and select Add Reference.... It should look something like:
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