user: Question: Name the date of appointment for 26 May 2011
Columns: ['Team', 'Outgoing manager', 'Manner of departure', 'Date of vacancy', 'Replaced by', 'Date of appointment', 'Position in table']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Deportivo La Coruña', 'Miguel Ángel Lotina', 'End of contract', '23 May 2011', 'José Luis Oltra', '27 May 2011', '18th (in La Liga )']
SQL:

assistant: SELECT "Date of appointment" FROM "Table" WHERE "Date of vacancy" = '26 May 2011';