Python在数据框中读取JSON

Question

I have an SQL database which has two columns. One has the timestamp, the other holds data in JSON format

for example df:

ts                           data
'2017-12-18 02:30:20.553'   {'name':'bob','age':10, 'location':{'town':'miami','state':'florida'}}
'2017-12-18 02:30:21.101'   {'name':'dan','age':15, 'location':{'town':'new york','state':'new york'}}         
'2017-12-18 02:30:21.202'   {'name':'jay','age':11, 'location':{'town':'tampa','state':'florida'}}

If I do the following :

df = df['data'][0]
print (df['name'].encode('ascii', 'ignore'))

I get :

'bob'

Is there a way I can get all of the data correspondings to a JSON key for the whole column?

(ie for the df column 'data' get 'name')

'bob'

'dan'

'jay'

Essentially I would like to be able to make a new df column called 'name'

Answer 1

You can use json_normalize ie

pd.io.json.json_normalize(df['data'])['name']

0    bob
1    dan
2    jay
Name: name, dtype: object

Answer 2

IIUC, lets use apply with lambda function to select value from dictionary by key:

df['data'].apply(lambda x: x['name'])

Output:

0    bob
1    dan
2    jay
Name: data, dtype: object