sql_queries.py

from configparser import ConfigParser, ExtendedInterpolation


# CONFIG
parser = ConfigParser(interpolation=ExtendedInterpolation())
parser.read('dwh.cfg')

# DROP TABLES

staging_events_table_drop = "DROP TABLE IF EXISTS staging_events"
staging_songs_table_drop = "DROP TABLE IF EXISTS staging_songs"
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

staging_events_table_create= """
CREATE TABLE IF NOT EXISTS staging_events (
    artist VARCHAR,
    auth VARCHAR,
    firstName VARCHAR,
    gender CHAR(1),
    itemInSession INT,
    lastName VARCHAR,
    length FLOAT,
    level VARCHAR,
    location TEXT,
    method VARCHAR,
    page VARCHAR,
    registration VARCHAR,
    sessionId INT,
    song VARCHAR,
    status INT,
    ts BIGINT,
    userAgent TEXT,
    userId INT
);
"""

staging_songs_table_create = """
CREATE TABLE IF NOT EXISTS staging_songs (
    artist_id VARCHAR,
    artist_latitude FLOAT,
    artist_location TEXT,
    artist_longitude FLOAT,
    artist_name VARCHAR,
    duration FLOAT,
    num_songs INT,
    song_id VARCHAR,
    title VARCHAR,
    year INT
);
"""

songplay_table_create = """
CREATE TABLE IF NOT EXISTS songplays (
    songplay_id INT IDENTITY(0, 1) PRIMARY KEY, -- act as SERIAL type of pure postgresql
    start_time TIMESTAMP,
    user_id INT,
    level VARCHAR,
    song_id VARCHAR,
    artist_id VARCHAR,
    session_id INT,
    location TEXT,
    user_agent TEXT
);
"""

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 FLOAT NOT NULL
);
"""

artist_table_create = """
CREATE TABLE IF NOT EXISTS artists (
    artist_id VARCHAR PRIMARY KEY,
    name VARCHAR NOT NULL,
    location TEXT,
    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 VARCHAR
);
"""

# STAGING TABLES

staging_events_copy = f"""
COPY staging_events
FROM '{parser.get('s3', 'log_data')}'
IAM_ROLE '{parser.get('iam.role', 'arn')}'
JSON '{parser.get('s3', 'log_jsonpath')}'
"""

staging_songs_copy = f"""
COPY staging_songs
FROM '{parser.get('s3', 'song_data')}'
IAM_ROLE '{parser.get('iam.role', 'arn')}'
JSON 'auto'
"""

# FINAL TABLES

songplay_table_insert = """
INSERT INTO songplays (start_time, user_id, level, song_id, artist_id, session_id, location, user_agent)
SELECT DISTINCT timestamp with time zone 'epoch' + se.ts/1000 * interval '1 second',
       se.userId, 
       se.level, 
       ss.song_id, 
       ss.artist_id, 
       se.sessionId, 
       se.location, 
       se.userAgent
FROM staging_events AS se INNER JOIN staging_songs AS ss
ON se.song = ss.title AND se.artist = ss.artist_name AND se.length = ss.duration
WHERE se.page = 'NextSong'
"""

user_table_insert = """
INSERT INTO users (user_id, first_name, last_name, gender, level)
SELECT DISTINCT userId, 
       firstName, 
       lastName, 
       gender, 
       level
FROM staging_events
WHERE page = 'NextSong' AND userId IS NOT NULL
"""

song_table_insert = """
INSERT INTO songs (song_id, title, artist_id, year, duration)
SELECT DISTINCT song_id, 
       title, 
       artist_id, 
       year, 
       duration
FROM staging_songs
WHERE song_id IS NOT NULL
"""

artist_table_insert = """
INSERT INTO artists (artist_id, name, location, latitude, longitude)
SELECT DISTINCT artist_id, 
       artist_name, 
       artist_location, 
       artist_latitude, 
       artist_longitude
FROM staging_songs
WHERE artist_id IS NOT NULL
"""

time_table_insert = """
INSERT INTO time (start_time, hour, day, week, month, year, weekday)
SELECT start_time, 
       extract(hour from start_time), 
       extract(day from start_time), 
       extract(week from start_time), 
       extract(month from start_time), 
       extract(year from start_time), 
       extract(weekday from start_time)
FROM songplays
"""

# QUERY LISTS

create_table_queries = [staging_events_table_create, staging_songs_table_create, songplay_table_create, user_table_create, song_table_create, artist_table_create, time_table_create]
drop_table_queries = [staging_events_table_drop, staging_songs_table_drop, songplay_table_drop, user_table_drop, song_table_drop, artist_table_drop, time_table_drop]
copy_table_queries = [staging_events_copy, staging_songs_copy]
insert_table_queries = [songplay_table_insert, user_table_insert, song_table_insert, artist_table_insert, time_table_insert]