text: insert into activity values (1, '2016-12-13', '12:00:00', '13:00:00',20, 'cours collectif relax');
  insert into activity values (2, '2016-12-15', '12:00:00', '13:00:00',30,'cours collectif tonic');
  insert into activity values (3, '2016-12-12', '12:00:00', '12:15:00',1, 'massage individuel assis');
  insert into activity values (4, '2016-12-12', '12:15:00', '12:30:00',1, 'massage individuel assis');
  
  insert into participation values (1, 'toto@toto.com',1);
  