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Useful links

• https://mariadb.com/kb/en/library/grant/

Stop mariadb server on Ubuntu 18.04

sudo service mariadb stop

Grant "root" rights for escobar in the database mydb

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Java common

Strings

Find a substring by a regular expression:

  String pattern = "(.*)(\\d\\d\\d\\d)(.*)";
  String line = "2018-11-22 00:00:00";
 Pattern re = Pattern.compile(pattern);

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Ffmpeg

• split a video to two files (the first part contains 5min and the second the rest) of the same type:

ffmpeg -i bigvideo.mp4 -t 00:05:00 -c copy bigvideo_part1.mp4 -ss 00:05:00 -c copy bigvideo_part2.mp4

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ImageMagick scripts

https://imagemagick.org

create a thumbnail of size 200x200 from an image keeping the aspect ratio

convert -define jpeg:size=200x200 source.jpg -thumbnail '100x100>' target.jpg

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# Copy all regular files in the current directory (including subdirectories) 
# to the given directory  

for x in `find -type f` ; do  `cp $x /home/escobar/Pictures`; done     

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Test

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Examples of Linux find

List all files in current and sub directories

Find recursively all files and directories in the current path:

find

Search specific directory or path

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$date = strtodate('-2 weeks', $unix_timestamp); 

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Tmux cheat sheet

(This a copy cheat sheet)

(C-x means ctrl+x, M-x means alt+x)

Prefix key

The default prefix is C-b. If you (or your muscle memory) prefer C-a, you need to add this to ~/.tmux.conf:

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Java Date

Examples

    String date = "2016-08-16";

    //default, ISO_LOCAL_DATE