Selecting values from a column with GQL in App Engine
I want to get the values from a particular column of a table. Whats the correct query for that ?
Eg: Suppose we have a Crisis table which has a "name" column
I want all the values in this column as a list
I tried "SELECT开发者_高级运维 name FROM Crisis" but it didnt work.
Edit:
Here is the exact code:
def get(self):
c = db.GqlQuery('SELECT name FROM Crisis')
Error message:
Traceback (most recent call last):
... c = db.GqlQuery('SELECT name FROM Crisis') ... BadQueryError: Parse Error: Expected no additional symbols at symbol nameYou can't select a single column from an entity. This is one of the most basic limitations of the App Engine datastore. You can retrieve the entire entity, or only its key.
def get(self):
c = db.GqlQuery('SELECT * FROM Crisis')
for entity in c:
logging.info(entity.name)
Edit: To be more precise, there are no "columns" in App Engine.
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