73 lines
2.1 KiB
Markdown
73 lines
2.1 KiB
Markdown
https://wiki.bash-hackers.org/
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Update PostgreSQL
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wget -q https://www.postgresql.org/media/keys/ACCC4CF8.asc -O - | sudo apt-key add -
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sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ `lsb_release -cs`-pgdg main" >> /etc/apt/sources.list.d/pgdg.list'
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sudo apt-get update
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sudo apt-get install postgres-10
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sudo su - postgres
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psql
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Set PSQL defaults
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put .psqlrc in home directory
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\set x '\\setenv PAGER less'
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\set xx '\\setenv PAGER \'pspg -bX --no-mouse\''
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Size of directory: `du -hcs //mnt/c/PostgreSQL/cassandra30/`
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list lines in file `wc file`
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General tasks
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wc - print line counts
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free - memory usage
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du - disk space by file
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Resource Limit
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`ulimit -a` to see all limits
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file at /etc/security/limits.conf to configure defaults
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MySQL
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connection like `mysql -u root -p`
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`show databases;`
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user is in the format root@127.0.0.1
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`grant all prviileges on *.* to 'root'@'127.0.0.1'`
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data is stored in /var/lib/mysql
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failure to drop a db can be due to presence of unknown file in the database directory
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SSH
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add client
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* client uses ssh-keygen to create a key in `/home/un/.ssh/` under files `id_rsa` and `id_rsa.pub`
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* host setup //etc/ssh/sshd_config to allow passwords and restart
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* client uses `ssh-copy-id host_address -p port_num` to move the key to the host
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* client uses `ssh` to login
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rename files in the current director
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rename 's/find_this_in_the_file_name/replace_with_this/g' *
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