CODEWITHSUNDEEP
python-2.7app-engine-ndb
user2495766
user2495766

Reputation: 123

app-engine ndb delete data

I'm new to app-engine [Python 2.7] I would like to delete elements from my ndb (currently I don't care if it is one by one or all at once since none is working for me).

Version 1 based on this Q:

ps_ancestors = req_query.fetch()
for ps_ancestor in ps_ancestors:
  self.response.write(ps_ancestor.key)
  ps_ancestor.key.delete()

It continues to print the same data without actually deleting anything

Version 2: [myId currently have only the values 1,2,3]

ndb.Key(myId, 1).delete()
ndb.Key(myId, 2).delete()  
ndb.Key(myId, 3).delete()

The model:

class tmpReport (ndb.Model):
    myId = ndb.IntegerProperty()
    hisId = ndb.IntegerProperty()
    date = ndb.DateTimeProperty(auto_now_add=True)

What am I missing?

Upvotes: 0

Views: 2502

Answers (3)

Zain Qasmi
Zain Qasmi

Reputation: 355

query1 = tmpReport.query()
query2 = query1.filter(tmpReport.myId == int(myId)) 
#Add other filters as necessary 
query3 = query2.fetch()
query3[0].key.delete()

Removes the first entity(element) returned assuming myID is unique so there is only one element in the list.

Upvotes: 0

Greivin López
Greivin López

Reputation: 121

First of all, you should not define your Entity key as an IntegerProperty. Take a look at this documentation: NDB Entities and Keys

In order to delete an entity from datastore you should first retrieve it by using a query or by its ID. I recommend you to use a "keyname" when creating your entities (to use it as your custom ID):

   # Model declaration
   class tmpReport (ndb.Model):
       hisId = ndb.IntegerProperty()
       date = ndb.DateTimeProperty(auto_now_add=True)

# Store the entity
   report = tmpReport(id=1, hisId=5)
   report.put()

Then to retrieve and delete the previous entity use:

# Retrieve entity
report = ndb.Key("tmpReport", 1).get()
# Delete the entity
report.key.delete()

Hope it helps.

Upvotes: 0

HimalayanCoder
HimalayanCoder

Reputation: 9850

k = users.query(users.name == 'abhinav')
for l in k.fetch(limit = 1):
    l.key.delete()

Upvotes: 2

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