Unsubscribe from youtube channel

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If we like youtube video and want to know future updates from that channel, then we have to subscribe

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Pipe %>% Operator in R

Pipe %>% Operator in R is used to sequence of multiple operations. Pipe operators, available in magrittr, dplyr, and other R packages. Aim of pipe is to increase the performance of operation.


1. Load dplyr(or magrittr) package.


How to rename database in Sybase

Stored procedure sp_renamedb is used to change the user database.

sp_renamedb dbname, new_name

dbname is existing database name.
new_name is the new database name.

Error: package or namespace load failed for ‘ggplot2’

I have installed ggplot2 package successfully. This error occurred while loading package using R function library.

Error in loadNamespace(j < - i[[1L]], c(lib.loc, .libPaths()), versionCheck = vI[[j]]) : there is no package called ‘Rcpp’ Error: package or namespace load failed for ‘ggplot2’ Troubleshooting Steps:

How to install ggplot2 package in R

What is ggplot2?

ggplot2 package is used to produce statistical, or data, graphics based on Grammar of Graphics. ggplot2 provides beautiful hassle-free plots. To use ggplot2,e have to install it. To use ggplot2 package, first we have to install it and then load it.

Install ggplot2 package in R:

1. Install ggplot2 package with R function install.packages(“package_name”)

How to stop and start MySQL server

To Stop MySQL Server

#sudo mysqld stop #service mysql stop #/etc/init.d/mysql stop #sudo service mysql stop #sudo /etc/init.d/mysql stop #/usr/local/mysql/bin/mysqladmin -u root -p shutdown

To Start MySQL Server

#sudo mysqld start # service mysql start # /etc/init.d/mysql start# # sudo service mysql start # sudo /etc/init.d/mysql start

To restart MySQL Server without running stop and start, use:

#sudo service mysql restart #sudo /etc/init.d/mysql restart

If any failures occurred in start or stop MySQL Server, please error information in error.log file.

root@ubuntu:/var/log/mysql# ls -ltrh total 36K -rw-r----- 1 mysql adm 1.8K Sep 9 20:25 error.log.7.gz -rw-r----- 1 mysql adm 256 Sep 10 05:20 error.log.6.gz -rw-r----- 1 mysql adm 286 Sep 11 01:18 error.log.5.gz -rw-r----- 1 mysql adm 347 Sep 12 05:54 error.log.4.gz -rw-r----- 1 mysql adm 2.5K Sep 13 19:18 error.log.3.gz -rw-r----- 1 mysql adm 285 Sep 14 03:23 error.log.2.gz -rw-r----- 1 mysql adm 4.8K Sep 15 02:22 error.log.1.gz -rw-r----- 1 mysql adm 2.1K Sep 15 21:11 error.log root@ubuntu:/var/log/mysql#

Replication Basic Commands in Sybase

Replication is an ongoing process of transferring completed transactions from primary database to the replicated database reading from the transaction logs creating an inbound and distributing the data through the outbound queue.

Replication Basic Commands in Sybase

admin who_is_down:it shows which servers are down
admin who_is_up : it shows which servers are up
admin who:shows all running process
admin rssd_name:shows the rep_server securityname

Create Role and assign permissions in Sybase

Roles are collections of privileges that allow the role user to perform their jobs. Roles can be created and granted to users, login profiles, or other roles by a system security officer. There are 16 default roles in ASE.


Syntax to Create Role:

Largest Tables in MySQL

Largest Tables in MySQL:

Following query will give largest tables of entire MySQL.

SELECT table_schema as 'Database', table_name AS 'Table', round(((data_length + index_length) / 1024 / 1024), 2) 'Size in MB' FROM information_schema.TABLES ORDER BY (data_length + index_length);


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