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,
    start_time TIMESTAMP NOT NULL,
    user_id INTEGER NOT NULL,
    level VARCHAR,
    song_id VARCHAR,
    artist_id VARCHAR,
    session_id INT,
    location VARCHAR,
    user_agent VARCHAR,
    UNIQUE(user_id, artist_id, song_id)
);
""")

user_table_create = ("""
CREATE TABLE IF NOT EXISTS users (
    user_id INTEGER PRIMARY KEY,
    first_name VARCHAR,
    last_name VARCHAR,
    gender VARCHAR,
    level VARCHAR
);
""")

song_table_create = ("""
CREATE TABLE IF NOT EXISTS songs (
    song_id VARCHAR PRIMARY KEY,
    title VARCHAR,
    artist_id VARCHAR,
    year INT,
    duration NUMERIC
);
""")

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

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 (to_timestamp(%s), %s, %s, %s, %s, %s, %s, %s)
""")

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 (to_timestamp(%s), %s, %s, %s, %s, %s, %s) ON CONFLICT (start_time) DO NOTHING;"

# FIND SONGS

song_select = "SELECT a.artist_id, song_id " \
              "FROM songs JOIN artists a on songs.artist_id = a.artist_id " \
              "WHERE title = %s AND a.name = %s AND duration = %s"

# QUERY LISTS

create_table_queries = [songplay_table_create, user_table_create, song_table_create, artist_table_create, time_table_create]
drop_table_queries = [songplay_table_drop, user_table_drop, song_table_drop, artist_table_drop, time_table_drop]