Mission: SQL feature query lab (step 6/7) · sql for ml datasets

Write feature_row(db, user, cutoff): return (n_valid, total) for one user before the cutoff — COUNT(amount) for valid rows, COALESCE'd SUM. Parameters via ? only.

Write summary_row(db, user, cutoff): return (n_valid, total) for one user before the cutoff — COUNT(amount) for valid rows, COALESCE'd SUM. Parameters via ? only.

Write feature_row(db, user, cutoff): return (n_valid, total) for one user before the cutoff — COUNT(amount) for valid rows, COALESCE'd SUM. Parameters via ? only.

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])

# define summary_row(db, user, cutoff) below

print(summary_row(db, "maya", "2026-03"))
print(summary_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

import sqlite3
db = sqlite3.connect(":memory:")
db.execute("CREATE TABLE events (user TEXT, month TEXT, amount REAL)")
db.executemany("INSERT INTO events VALUES (?, ?, ?)", [
    ("maya", "2026-01", 40.0), ("maya", "2026-02", 60.0),
    ("marcus", "2026-01", 10.0), ("marcus", "2026-03", 30.0),
    ("riley", "2026-02", None),
])


# define feature_row(db, user, cutoff) below

print(feature_row(db, "maya", "2026-03"))
print(feature_row(db, "riley", "2026-03"))

Write feature_row(db, user, cutoff): return (n_valid, total) for one user before the cutoff — COUNT(amount) for valid rows, COALESCE'd SUM. Parameters via ? only.

Write summary_row(db, user, cutoff): return (n_valid, total) for one user before the cutoff — COUNT(amount) for valid rows, COALESCE'd SUM. Parameters via ? only.

Write feature_row(db, user, cutoff): return (n_valid, total) for one user before the cutoff — COUNT(amount) for valid rows, COALESCE'd SUM. Parameters via ? only.

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Mission: SQL feature query lab — step 6 of 7