create_tables.py

import psycopg2
from sql_queries import create_table_queries, drop_table_queries


def create_database():
    """Create the spartifydb database.
    If it already exists, Drop and create the database.

    Returns:
        cursor(psycopg2.cursor): The psycopg2 cursor
        connection(psycopg2.connection): The sparkifydb connection
    """
    # connect to default database
    conn = psycopg2.connect(
        "host=127.0.0.1 dbname=studentdb user=student password=student"
    )
    conn.set_session(autocommit=True)
    cur = conn.cursor()

    # create sparkify database with UTF8 encoding
    cur.execute("DROP DATABASE IF EXISTS sparkifydb")
    cur.execute(
        "CREATE DATABASE sparkifydb WITH ENCODING 'utf8' TEMPLATE template0"
    )

    # close connection to default database
    conn.close()

    # connect to sparkify database
    conn = psycopg2.connect(
        "host=127.0.0.1 dbname=sparkifydb user=student password=student"
    )
    cur = conn.cursor()

    return cur, conn


def drop_tables(cur, conn):
    """Read DROP queries from `sql_queries.drop_table_queries` and execute them.

    Args:
        cur (psycopg2.cursor): The psycopg2 cursor
        conn (psycopg2.connection): The Database connection
    """
    for query in drop_table_queries:
        cur.execute(query)
        conn.commit()


def create_tables(cur, conn):
    """Read CREATE queries from `sql_queries.create_table_queries` and execute them

    Args:
        cur (psycopg2.cursor): The psycopg2 cursor
        conn (psycopg2.connection): The Database connection
    """
    for query in create_table_queries:
        cur.execute(query)
        conn.commit()


def main():
    cur, conn = create_database()

    drop_tables(cur, conn)
    create_tables(cur, conn)

    conn.close()


if __name__ == "__main__":
    main()