如何在不使用熊猫的情况下实施自然加入

Question

• 应使用单个功能

  完成

• 不应使用熊猫或合并函数或任何其他内置数据库库

Answer 1

您可以使用诸如psycopg2之类的本机驱动程序进行postgres https：> https://www.psycopg.org/docs/usage/usage/usage .html

import psycopg2

# Connect to an existing database
conn = psycopg2.connect("dbname=test user=postgres")
cur = conn.cursor()



# Query the database and obtain data as Python objects
cur.execute("""
SELECT * FROM test t
left join test1 t1 on (t.t1_id = t1.id);
""")
fetched_rows = cur.fetchall()


# Make the changes to the database persistent
conn.commit()

# Close communication with the database
cur.close()
conn.close()