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Andy McDonald
Python Development Techdegree Graduate 13,801 PointsHow to identify empty query object when empty query is truthy?
Working on the project and if the app searches for a book thats not in the database I would like the app to say so. The best way I know how to do so is like so:
def delete():
todel = input("What's the title of the book you want to delete?")
dellie = models.session.query(models.Book).filter_by(title=todel)
if dellie:
for book in dellie:
models.session.delete(book)
models.session.commit()
print('Alright that book is gone. Now what?')
else:
print('Cant find a book by that name. Try again.')
However, when I input a book title that does not exist it returns a query object that is truthy. Any suggestions?
[MOD: added ```python formatting -cf]
1 Answer
Chris Freeman
Treehouse Moderator 68,423 PointsHey Andy McDonald, then query method count() gives the size of the query result.
if dellie.count() > 0:
# OR in truthy fashion
if dellie.count():
Post back if you need more help. Good luck!!!