Working with Data Sources 9
Posted 阿难的机器学习计划
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1. One to many relations:
one value in column in table one related to several values in the column in table two. In this case, we need to be very clear that who is "one" and who is "many":
cursor = conn.cursor()
query =‘‘‘SELECT ceremonies.year,nominations.movie # select target column we want to fit into the query
FROM nominations # select table from the ‘one‘ table
INNER JOIN ceremonies #select table from the ‘many‘ table
ON ceremonies.id == nominations.ceremony_id # select revelent column
WHERE nominations.nominee == "Natalie Portman"; # select conditions we would like to query
‘‘‘
cursor.execute(query)
portman_movies = cursor.fetchall()
2.
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