Commands by cuberri (3)

  • This command drops all the sequences of the 'public' schema from the database. First, it constructs a 'drop sequence' instruction for each table found in the schema, then it pipes the result to the psql interactive command. See it scripted here : https://gist.github.com/cuberri/6868774#file-postgresql-drop-create-sh


    0
    psql -h <ph_host> -p <pg_port> -U <pg_user> <pg_db> -t -c "select 'drop sequence \"' || relname || '\" cascade;' from pg_class where relkind='S'" | psql -h <ph_host> -p <pg_port> -U <pg_user> <pg_db>
    cuberri · 2013-12-11 15:42:34 0
  • This command drops all the tables of the 'public' schema from the database. First, it constructs a 'drop table' instruction for each table found in the schema, then it pipes the result to the psql interactive command. Useful when you have to recreate your schema from scratch in development for example. I mainly use this command in conjunction with a similar command which drop all sequences as well. Example : psql -h <pg_host> -p <pg_port> -U <pg_user> <pg_db> -t -c "select 'drop table \"' || tablename || '\" cascade;' from pg_tables where schemaname='public'" | psql -h <pg_host> -p <pg_port> -U <pg_user> <pg_db> psql -h <ph_host> -p <pg_port> -U <pg_user> <pg_db> -t -c "select 'drop sequence \"' || relname || '\" cascade;' from pg_class where relkind='S'" | psql -h <ph_host> -p <pg_port> -U <pg_user> <pg_db> See it scripted here : https://gist.github.com/cuberri/6868774#file-postgresql-drop-create-sh


    0
    psql -h <pg_host> -p <pg_port> -U <pg_user> <pg_db> -t -c "select 'drop table \"' || tablename || '\" cascade;' from pg_tables where schemaname='public'" | psql -h <pg_host> -p <pg_port> -U <pg_user> <pg_db>
    cuberri · 2013-12-11 15:39:56 0
  • Useful when you want to cron a daily deletion task in order to keep files not older than one year. The command excludes .snapshot directory to prevent backup deletion. One can append -delete to this command to delete the files : find /path/to/directory -not \( -name .snapshot -prune \) -type f -mtime +365 -delete


    1
    find /path/to/directory -not \( -name .snapshot -prune \) -type f -mtime +365
    cuberri · 2013-12-11 14:51:53 0

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

matrix in your term
-a : Asynchronous scroll -b : Bold characters on -x : X window mode, use if your xterm is using mtx.pcf

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

draw matrix using dot

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

get rid of lines with non ascii characters
found here: https://stackoverflow.com/a/9035939

type fortune in real time

Selecting a random file/folder of a folder
Also looks in subfolders

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Ensure that each machine that you log in to has its own history file
On systems where your home directory is shared across different machines, your bash history will be global, rather than being a separate history per machine. This setting in your .bashrc file will ensure that each machine has its own history file.

Create a 100MB file for testing transfer speed


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: