Backup and restore MySQL database

To backup a MySQL database

See this link here

shell> mysqldump [arguments] > file_name
shell> mysqldump --all-databases > dump.sql

shell> mysqldump --triggers --routines --all-databases > dump.sql  
shell> mysqldump --databases db1 db2 db3 > dump.sql

shell> mysqldump --databases dbname > dump.sql

OR omit the --databases

shell> mysqldump test > dump.sql

To dump only specific tables from a database use;

shell> mysqldump dbmane table1 table3 table7 > dump.sql

To dump only the structure from a database use;

shell> mysqldump --no-data dbmane > dump.sql 

shell> mysqldump --d dbmane > dump.sql  

Note: -d includes the triggers. 

To dump only the routines from a all databases use;

mysqldump -u username -p -n -t -d -R --all-databases > routines.sql
 
To add the host 192.168.254.198 and the user root, do;

shell> mysqldump --host=192.168.254.198 --port=3307 -u root -p dbmane > dump.sql

See also my post here for details on how to simply copy the table structure.

Real examples with my_db:

The following will backup the structure, triggers, functions and procedures; 
mysqldump --host=[...] -udev -p --no-data --triggers --routines my_db > my_db_structure.sql

 

The following will backup the entire database, as above but including the data;

mysqldump --host=[...] -udev -p --triggers --routines my_db > my_db_all.sql

To restore a MySQL database

See this link here

shell> mysql -u root -p < dump.sql

Within mysql (first login, see below);

mysql> source dump.sql

To login to mysql, do;
mysql -u username -p

If the dump file does not create the database, then this must first be created;

shell> mysqladmin create dbname

Within mysql (this works for me);

mysql> CREATE DATABASE IF NOT EXISTS dbname; mysql> USE dbname; mysql> source dump.sql

Real example with my_db:

Firstly, ensure the database has been created by logging in and doing:

 

CREATE DATABASE mydb;

 

then;

 

mysql --host=[...] -udev -p my_db < my_db_all.sql

 

 

To backup and restore database users and grants, see here

Convert PostgreSQL database to MySQL

To convert from a PostgreSQL database to MySQL;

Check out this link

Connect to Postgres database with php

This extension enables PHP to connect to and use PostgreSQL databases.

This is specifically for Slackware.

1)  install php-pgsql

Slackbuild install file ready for 14.2 here

Slack build page here

2) To enable the pgsql extension for php, go to /etc/php.d/pgsql.iniand uncomment the line:

; extension=pgsql.so

Physical memory modules installed in Linux

The following commands will help determine the number and size of memory modules installed in a Linux system.

dmidecode -t memory

dmidecode -t memory | grep -i size

dmidecode -t 16

dmidecode -t 17

lshw -class memory

Java Netbeans project.properties, manifest file, code signing certificates and jnlp files.

In the project folder, project/nbproject/project.properties we can modify various attributes that affect the project properties, such as;

See the # Optional override of default tags.

manifest.custom.permissions=all-permissions

Specifically if using a jnlp file, then the permissions and codebase options should match otherwise Java security might not allow application to launch.

In Netbeans, under webstart, choose user defined and enter full codebase, also note this post re having different jar files with different certificates.

For more details, see here:
https://blog.david14.com/2020/07/application-blocked-by-java-security.html

See here for a walkthrough; https://docs.oracle.com/javase/tutorial/deployment/webstart/deploying.html

Also see here: https://www.oracle.com/technical-resources/articles/javase/ds-jnlp-javawebstart.html

Printing via UDP in Python

TO BE TESTED

import socket
import system
udpSocket=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
message ="SEND THIS TO ZEBRA"
ip='192.168.0.100'
port=20000
udpSocket.sendto(message,(ip,port))

Socket clientSocket = new Socket(AddressFamily.InterNetwork,

SocketType.Stream, ProtocolType.Tcp);
clientSocket.NoDelay = true;

IPAddress ip = IPAddress.Parse("192.168.192.6");
IPEndPoint ipep = new IPEndPoint(ip, 9100);
clientSocket.Connect(ipep);

byte[] fileBytes = File.ReadAllBytes("test.txt");

clientSocket.Send(fileBytes);
clientSocket.Close(); 

Cisco SG200-08

To reset to Factory Settings.

Find large files in Linux

The following will list the top 10 files by size in a dir

find /path/to/dir/ -printf '%s %p\n'| sort -nr | head -10

The k option shows file size in kb

find /path/to/dir/ -printf '%k %p\n'| sort -nr | head -10 

local http servers

The following starts a basic http server locally in the current directory;

python 2.x

python -m SimpleHTTPServer 8080

python 3.x (untested)

python -m http.server 8080

https://gist.github.com/willurd/5720255

Linux memory usage by percentage

This will show the memory usage, ordered by percentage;

ps -o pid,user,%mem,command ax | sort -b -k3 -r | less