Drop databases selectively by matching any part of the name. (https://github.com/Kraymer/ezdropdb)

ezdropdb

#!/bin/bash

# Copyright (c) 2017 Fabrice Laporte - kray.me
# The MIT License http://www.opensource.org/licenses/mit-license.php

# ezdropdb
# Removes PostgreSQL databases selectively by matching any part of the name.

readonly PROGNAME=$(basename $0)

usage() {
    cat << EOF
USAGE: $PROGNAME [-s signal_name] pattern

    $PROGNAME lists all databases that match the criteria given on the command line, prefixed by
    an identifier.
    It then prompts you for which databases to drop by entering corresponding identifiers.

    OPTIONS:
        see 'dropdb' USAGE
EOF
}

# Print array elements, one per line, prefixed by a letter identifier from a to z.
# Alternate lines background colours for best readability.
#
# $@ - array to print
print_alternate()
{
    ps_grep_lines=("$@")
    if [ ${#ps_grep_lines[@]} -eq 0 ]; then
        echo "No databases found."
        exit 0
    fi
    CTRL_REVERSE="\e[7m"
    CTRL_RESET="\e[27m"
    LINE_IDX=a
    for ((i = 0; i < ${#ps_grep_lines[@]}; ++i)); do
        cmd=`echo ${ps_grep_lines[$i]} | cut -f 2-99 -d " " | cut -c 1-128`
        ((i % 2 == 0)) && printf "${LINE_IDX}"
        ((i % 2 != 0)) && printf "${CTRL_REVERSE}${LINE_IDX}${CTRL_RESET}"
        echo " ${cmd}"
        LINE_IDX=$(echo "$LINE_IDX" | tr "0-9a-z" "1-9a-z_")  # alpha increment
        if [ $i -eq 25 ]; then
            echo '...'
            break
        fi
    done
}

ezdropdb() {
    options=${@:1:$#-1}  # all args but last
    while IFS= read -r line; do
        if [ ! -z "$line" -a "$line" != " " ]; then
            databases+=("$line")
        fi
    done < <( psql $options -tl|cut -d'|' -f 1|sed -e '/^ *$/d'|grep -e "${@: -1}" | grep -v "$0" )

    print_alternate "${databases[@]}"
    echo " "
    read -p "Drop databases: " cmd_ids
    for (( i=0; i<${#cmd_ids}; i++ )); do
        ascii_cmd_id=`printf "${cmd_ids:$i:1}" | od -A n -t d1`
        idx=`expr $ascii_cmd_id - 97`
        dbname=`echo ${ps_grep_lines[$idx]}`
        dropdb $options $dbname
    done
}


main() {
    ezdropdb $@
}
main $@