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Remove an entire column from a data.frame in R
...=4:6)
to remove just the a column you could do
Data <- subset( Data, select = -a )
and to remove the b and d columns you could do
Data <- subset( Data, select = -c(d, b ) )
You can remove all columns between d and b with:
Data <- subset( Data, select = -c( d : b )
As I said above...
What is the difference between HAVING and WHERE in SQL?
What is the difference between HAVING and WHERE in an SQL SELECT statement?
20 Answers
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Select all columns except one in MySQL?
I'm trying to use a select statement to get all of the columns from a certain MySQL table except one. Is there a simple way to do this?
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Is there a function to deselect all text using JavaScript?
Is there a function in javascript to just deselect all selected text? I figure it's got to be a simple global function like document.body.deselectAll(); or something.
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C: Run a System Command and Get Output? [duplicate]
I want to run a command in linux and get the text returned of what it outputs, but I do not want this text printed to screen. Is there a more elegant way than making a temporary file?
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How to create .ipa file using Xcode?
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In Xcode Version 10.0
Go to Window -> Organizer
Then select your app archive from archives
Then click the "Distribute App" button on right panel
Then follow the below steps
Step 1
Step 2
Step 3
Step 4
Step 5
Step 6 : Finally select the place you want to sa...
Using column alias in WHERE clause of MySQL query produces an error
... though, by putting the expression directly into the WHERE x IN y clause:
SELECT `users`.`first_name`,`users`.`last_name`,`users`.`email`,SUBSTRING(`locations`.`raw`,-6,4) AS `guaranteed_postcode`
FROM `users` LEFT OUTER JOIN `locations`
ON `users`.`id` = `locations`.`user_id`
WHERE SUBSTRING(`loca...
How to round an average to 2 decimal places in PostgreSQL?
... round that takes a precision is only available for numeric.
regress=> SELECT round( float8 '3.1415927', 2 );
ERROR: function round(double precision, integer) does not exist
regress=> \df *round*
List of functions
Schema | Name | Result data type | Argument...
How to set Sqlite3 to be case insensitive when string comparing?
I want to select records from sqlite3 database by string matching. But if I use '=' in the where clause, I found that sqlite3 is case sensitive. Can anyone tell me how to use string comparing case-insensitive?
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Can someone explain collection_select to me in clear, simple terms?
I am going through the Rails API docs for collection_select and they are god-awful.
2 Answers
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