kdb: 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/kdb - from package: elektra-bin

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

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