Table: manager_changes_1999
Columns: team
outgoing_manager
manner_of_departure
date_of_vacancy
replaced_by
date_of_appointment

Question: When was the date of appointment for St. Johnstone's manager? 
SQL: SELECT "date_of_appointment" FROM manager_changes_1999 WHERE "team" = 'St. Johnstone'

Question: Who was the outgoing manager for Aberdeen? 
SQL: SELECT "outgoing_manager" FROM manager_changes_1999 WHERE "team" = 'Aberdeen'

Question: When was the date of appointment for the manager replacing Wim Jansen? 
SQL: SELECT "date_of_appointment" FROM manager_changes_1999 WHERE "outgoing_manager" = 'Wim Jansen'