SQlite query with datetime doesn't work

Question

Hi, I'm working on an iPhone app. I've tried to make a simple query that works correctly on sqlite console but it doesn't work on my iPhone code.

This works and it show me all the fields:

const char *sqlStatement = "sessions * from animals";

This doesn't show anything, but works correctly on sql console:

const char *sqlStatement = "select * from sessions where date>datetime('now','-7 days')";

Thanks for your help.