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How do I delete rows in a data frame?
...ou can delete rows of a data.frame by number as per the top answer. I.e.,
newdata <- myData[-c(2, 4, 6), ]
However, if you are trying to write a robust data analysis script, you should generally avoid deleting rows by numeric position. This is because the order of the rows in your data may c...
How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
...ike INSERT, except that if an old row in the table has the same value as a new row for a PRIMARY KEY or a UNIQUE index, the old row is deleted before the new row is inserted.
Note this is not standard SQL. An example from the manual:
CREATE TABLE test (
id INT UNSIGNED NOT NULL AUTO_INCREMENT,...
How to find out what group a given user has?
...l = function(e) {
var $elem = $('.new-login-left'),
docViewTop = $window.scrollTop(),
docViewBottom = docViewTop + $window.height(),
...
How to convert SSH keypairs generated using PuTTYgen (Windows) into key-pairs used by ssh-agent and
...
I assume this is something new, but if you open your private key in puttygen, then it will automatically show you an OpenSSH compatible, copyable, public key string in the UI.
– UpTheCreek
May 3 '15 at 18:55
...
findViewById in Fragment
...s is the correct way to setup listeners on fragments... Perhaps this was a new development in the API.
– Sonny
Oct 8 '14 at 22:11
...
How do I align views at the bottom of the screen?
...on that will be aligned to the end and the bottom of the screen.
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_h...
SQL WHERE.. IN clause multiple columns
...o this derived table:
select * from table1 LEFT JOIN
(
Select CM_PLAN_ID, Individual_ID
From CRM_VCM_CURRENT_LEAD_STATUS
Where Lead_Key = :_Lead_Key
) table2
ON
table1.CM_PLAN_ID=table2.CM_PLAN_ID
AND table1.Individual=table2.Individual
WHERE table2.CM_PLAN_ID IS NOT NULL
...
Passing an array as a function parameter in JavaScript
...
In ES6 standard there is a new spread operator ... which does exactly that.
call_me(...x)
It is supported by all major browsers except for IE.
The spread operator can do many other useful things, and the linked documentation does a really good job ...
Renew Provisioning Profile
...g profile for one of my apps is about to expire. Is there some way I can renew the existing one or must I recreate a new one?
...
Is JavaScript guaranteed to be single-threaded?
... it can be possible for someone to write a javascript api that also spawns new javascript threads, but the api would be rhino-specific (e.g. node can only spawn a new process).
I imagine that even for an engine that supports multiple threads in javascript there should be compatibility with scripts t...