apop_db_to_crosstab: 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/apop_db_to_crosstab - from package: apophenia-bin

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

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