Test Case: python-instruct-1603

  1import sqlite3  2​  3def fetch_single_record(db_path: str, table_name: str, column_name: str, value: any) -> tuple | None:  4    """  5    Fetches a single record from a SQLite database table based on a given condition.  6​  7    Args:  8        db_path: The path to the SQLite database file.  9        table_name: The name of the table to query. 10        column_name: The name of the column to use for filtering. 11        value: The value to match in the specified column. 12​ 13    Returns: 14        A tuple representing the single fetched record, or None if no record is found. 15    """ 16    conn = None 17    try: 18        conn = sqlite3.connect(db_path) 19        cursor = conn.cursor() 20​ 21        query = f"SELECT * FROM {table_name} WHERE {column_name} = ?" 22        cursor.execute(query, (value,)) 23        record = cursor.fetchone() 24        return record 25    except sqlite3.Error as e: 26        print(f"Database error: {e}") 27        return None 28    finally: 29        if conn: 30            conn.close() 31​ 32if __name__ == '__main__': 33    # Example Usage: 34​ 35    # Create a dummy database and table for demonstration 36    db_file = "my_database.db" 37    conn = sqlite3.connect(db_file) 38    cursor = conn.cursor() 39    cursor.execute("DROP TABLE IF EXISTS users") 40    cursor.execute("CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT, age INTEGER)") 41    cursor.execute("INSERT INTO users (name, age) VALUES (?, ?)", ("Alice", 30)) 42    cursor.execute("INSERT INTO users (name, age) VALUES (?, ?)", ("Bob", 25)) 43    cursor.execute("INSERT INTO users (name, age) VALUES (?, ?)", ("Charlie", 35)) 44    conn.commit() 45    conn.close() 46​ 47    # Fetch a record by ID 48    user_id_to_find = 2 49    record_by_id = fetch_single_record(db_file, "users", "id", user_id_to_find) 50    if record_by_id: 51        print(f"Record found by ID {user_id_to_find}: {record_by_id}") 52    else: 53        print(f"No record found with ID {user_id_to_find}") 54​ 55    # Fetch a record by name 56    user_name_to_find = "Alice" 57    record_by_name = fetch_single_record(db_file, "users", "name", user_name_to_find) 58    if record_by_name: 59        print(f"Record found by name '{user_name_to_find}': {record_by_name}") 60    else: 61        print(f"No record found with name '{user_name_to_find}'") 62​ 63    # Fetch a non-existent record 64    user_id_non_existent = 10 65    record_non_existent = fetch_single_record(db_file, "users", "id", user_id_non_existent) 66    if record_non_existent: 67        print(f"Record found by ID {user_id_non_existent}: {record_non_existent}") 68    else: 69        print(f"No record found with ID {user_id_non_existent}") 70​ 71    # Clean up the dummy database file 72    import os 73    os.remove(db_file)

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  1import sqlite3  2​  3def fetch_single_record(db_path: str, table_name: str, column_name: str, value: any) -> dict | None:  4    """  5    Fetches a single record from a SQLite database table based on a given condition.  6​  7    Args:  8        db_path: The path to the SQLite database file.  9        table_name: The name of the table to query. 10        column_name: The name of the column to filter by. 11        value: The value to match in the specified column. 12​ 13    Returns: 14        A dictionary representing the fetched record, or None if no record is found. 15    """ 16    conn = None 17    try: 18        conn = sqlite3.connect(db_path) 19        conn.row_factory = sqlite3.Row  # Return rows as dictionary-like objects 20        cursor = conn.cursor() 21​ 22        # Construct the SQL query securely using parameterization 23        query = f"SELECT * FROM {table_name} WHERE {column_name} = ?" 24        cursor.execute(query, (value,)) 25        row = cursor.fetchone() 26​ 27        if row: 28            return dict(row) 29        else: 30            return None 31    except sqlite3.Error as e: 32        print(f"Database error: {e}") 33        return None 34    finally: 35        if conn: 36            conn.close() 37​ 38if __name__ == '__main__': 39    # Example Usage: 40    # Create a dummy database and table for demonstration 41    DB_FILE = "test_database.db" 42    try: 43        conn = sqlite3.connect(DB_FILE) 44        cursor = conn.cursor() 45        cursor.execute("DROP TABLE IF EXISTS users") 46        cursor.execute(""" 47            CREATE TABLE users ( 48                id INTEGER PRIMARY KEY AUTOINCREMENT, 49                username TEXT NOT NULL UNIQUE, 50                email TEXT NOT NULL 51            ) 52        """) 53        cursor.execute("INSERT INTO users (username, email) VALUES (?, ?)", ("alice", "alice@example.com")) 54        cursor.execute("INSERT INTO users (username, email) VALUES (?, ?)", ("bob", "bob@example.com")) 55        conn.commit() 56        conn.close() 57​ 58        # Fetch a record 59        user_record = fetch_single_record(DB_FILE, "users", "username", "alice") 60        if user_record: 61            print("Fetched record:", user_record) 62        else: 63            print("Record not found.") 64​ 65        # Fetch a non-existent record 66        non_existent_record = fetch_single_record(DB_FILE, "users", "username", "charlie") 67        if non_existent_record: 68            print("Fetched record:", non_existent_record) 69        else: 70            print("Record not found.") 71​ 72    except sqlite3.Error as e: 73        print(f"Error during example setup or execution: {e}") 74    finally: 75        # Clean up the dummy database file 76        import os 77        if os.path.exists(DB_FILE): 78            os.remove(DB_FILE)

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