sql_queries.py

# DROP TABLES

songplay_table_drop = "DROP table IF EXISTS songplays"
user_table_drop = "DROP table IF EXISTS users"
song_table_drop = "DROP table IF EXISTS songs"
artist_table_drop = "DROP table IF EXISTS artists"
time_table_drop = "DROP table IF EXISTS time"

# CREATE TABLES

songplay_table_create = ("""
    CREATE TABLE IF NOT EXISTS songplays (
    songplay_id SERIAL PRIMARY KEY , 
    start_time timestamp NOT NULL REFERENCES time(start_time), 
    user_id int NOT NULL REFERENCES users(user_id), 
    level varchar, 
    song_id varchar REFERENCES songs(song_id), 
    artist_id varchar REFERENCES artists(artist_id), 
    session_id int, 
    location varchar, 
    user_agent varchar);
""") 

user_table_create = ("""
    CREATE TABLE IF NOT EXISTS users (
    user_id int PRIMARY KEY, 
    first_name varchar, 
    last_name varchar, 
    gender char(1), 
    level varchar);
""")

song_table_create = ("""
    CREATE TABLE IF NOT EXISTS songs (
    song_id varchar PRIMARY KEY, 
    title varchar NOT NULL, 
    artist_id varchar NOT NULL, 
    year int, 
    duration numeric NOT NULL);
""")

artist_table_create = ("""
    CREATE TABLE IF NOT EXISTS artists (
    artist_id varchar PRIMARY KEY , 
    name varchar NOT NULL, 
    location varchar, 
    latitude float, 
    longitude float);
""")

time_table_create = ("""
    CREATE TABLE IF NOT EXISTS time (
    start_time timestamp PRIMARY KEY, 
    hour int, 
    day int, 
    week int, 
    month int, 
    year int, 
    weekday int);
""")


# INSERT RECORDS

songplay_table_insert = ("""INSERT INTO songplays
    (start_time, user_id, level, song_id, artist_id, session_id, location, user_agent)
VALUES
    (%s, %s, %s, %s, %s, %s, %s, %s)
ON CONFLICT (songplay_id) DO NOTHING        
""")

user_table_insert = ("""INSERT INTO users
    (user_id, first_name, last_name, gender, level)
VALUES
    (%s, %s, %s, %s, %s)
ON CONFLICT(user_id) 
DO UPDATE 
    SET level = excluded.level
""")

song_table_insert = ("""INSERT INTO songs
    (song_id, title, artist_id, year, duration)
VALUES
    (%s, %s, %s, %s, %s)
ON CONFLICT (song_id) DO NOTHING    
""")

artist_table_insert = ("""INSERT INTO artists
    (artist_id, name, location, latitude, longitude)
VALUES
    (%s, %s, %s, %s, %s)
ON CONFLICT (artist_id) DO NOTHING
""")


time_table_insert = ("""INSERT INTO time
    (start_time, hour, day, week, month, year, weekday)
VALUES
    (%s, %s, %s, %s, %s, %s, %s)
ON CONFLICT (start_time) DO NOTHING    
""")

# FIND SONGS

song_select = (""" SELECT song_id, songs.artist_id \
                   FROM songs \
                   JOIN artists \
                   ON songs.artist_id = artists.artist_id \
                   WHERE title = %s \
                   AND name = %s \
                   AND duration = %s;                   
""")

# QUERY LISTS

create_table_queries = [user_table_create, song_table_create, artist_table_create, time_table_create, songplay_table_create]

drop_table_queries = [songplay_table_drop, user_table_drop, song_table_drop, artist_table_drop, time_table_drop]