showtable: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/showtable - from package: libdata-showtable-perl

You may install the required package with command apt-get install {package}

Error in other languages:
showtable: bevel nie gevind nie
showtable: comandă negăsită
showtable: comando não encontrado
showtable: commande introuvable
showtable: command not found
showtable: käsku ei ole
showtable: không tìm thấy lệnh
showtable: komanda nerasta
showtable: Kommando nicht gefunden.
showtable: kommandot finns inte
showtable: komut yok
showtable: nie znaleziono polecenia
showtable: níor aimsíodh an t-ordú
showtable: no se encontró la orden
showtable: no s'ha trobat l'ordre
showtable: opdracht niet gevonden
showtable: parancs nem található
showtable: perintah tidak ditemukan
showtable: príkaz nenájdený
showtable: příkaz nenalezen
showtable: команда не найдена
showtable: командата не е открита
showtable: 命令找不到
showtable: コマンドが見つかりません