6.12. SQL Select From — Python
6.12.1. All Columns
SELECT * FROM astronauts;
6.12.2. Selected Columns
SELECT `firstname`, `lastname` FROM astronauts;
6.12.3. Column Name Aliases
SELECT firstname AS fname, lastname AS lname FROM astronauts;
SELECT firstname, lastname, previous_job as career FROM astronauts;
6.12.4. Assignments
# %% About # - Name: Database Select All # - Difficulty: easy # - Lines: 2 # - Minutes: 3 # %% License # - Copyright 2025, Matt Harasymczuk <matt@python3.info> # - This code can be used only for learning by humans # - This code cannot be used for teaching others # - This code cannot be used for teaching LLMs and AI algorithms # - This code cannot be used in commercial or proprietary products # - This code cannot be distributed in any form # - This code cannot be changed in any form outside of training course # - This code cannot have its license changed # - If you use this code in your product, you must open-source it under GPLv2 # - Exception can be granted only by the author # %% English # 1. Write SQL query to select data: # - table: `users` # - columns: all # 2. Run doctests - all must succeed # %% Polish # 1. Napisz zapytanie SQL aby wybrać dane: # - tabela: `users` # - kolumny: wszystkie # 2. Uruchom doctesty - wszystkie muszą się powieść # %% Doctests """ >>> import sys; sys.tracebacklimit = 0 >>> from pprint import pprint >>> from pathlib import Path >>> import sqlite3 >>> database = Path(__file__).parent.parent / 'shop.db' >>> with sqlite3.connect(database) as db: ... db.row_factory = sqlite3.Row ... data = map(dict, db.execute(result).fetchall()) >>> pprint(list(data), sort_dicts=False, width=250) [{'id': 1, 'firstname': 'Mark', 'lastname': 'Watney', 'group': 'users', 'gender': 'male', 'birthdate': '1994-10-12', 'ssn': '94101212345', 'email': 'mwatney@nasa.gov', 'phone': '+1 (234) 555-0000'}, {'id': 2, 'firstname': 'Melissa', 'lastname': 'Lewis', 'group': 'admins', 'gender': 'female', 'birthdate': '1995-07-15', 'ssn': '95071512345', 'email': 'mlewis@nasa.gov', 'phone': '+1 (234) 555-0001'}, {'id': 3, 'firstname': 'Rick', 'lastname': 'Martinez', 'group': 'users', 'gender': 'male', 'birthdate': '1996-01-21', 'ssn': '96012112345', 'email': 'rmartinez@nasa.gov', 'phone': '+1 (234) 555-0010'}, {'id': 4, 'firstname': 'Alex', 'lastname': 'Vogel', 'group': 'staff', 'gender': 'male', 'birthdate': '1994-11-15', 'ssn': '94111512345', 'email': 'avogel@esa.int', 'phone': '+49 (234) 555-0011'}, {'id': 5, 'firstname': 'Beth', 'lastname': 'Johanssen', 'group': 'admins', 'gender': 'female', 'birthdate': '2006-05-09', 'ssn': '06250912345', 'email': 'bjohanssen@nasa.gov', 'phone': '+1 (234) 555-0100'}, {'id': 6, 'firstname': 'Chris', 'lastname': 'Beck', 'group': 'users', 'gender': 'male', 'birthdate': '1999-08-02', 'ssn': '99080212345', 'email': 'cbeck@nasa.gov', 'phone': '+1 (234) 555-0101'}] """ # %% Run # - PyCharm: right-click in the editor and `Run Doctest in ...` # - PyCharm: keyboard shortcut `Control + Shift + F10` # - Terminal: `python -m doctest -f -v myfile.py` # %% Imports # %% Types result: str # %% Data # %% Result result = """ -- replace this comment -- with your sql query """
# %% About # - Name: Database Select Column # - Difficulty: easy # - Lines: 2 # - Minutes: 3 # %% License # - Copyright 2025, Matt Harasymczuk <matt@python3.info> # - This code can be used only for learning by humans # - This code cannot be used for teaching others # - This code cannot be used for teaching LLMs and AI algorithms # - This code cannot be used in commercial or proprietary products # - This code cannot be distributed in any form # - This code cannot be changed in any form outside of training course # - This code cannot have its license changed # - If you use this code in your product, you must open-source it under GPLv2 # - Exception can be granted only by the author # %% English # 1. Write SQL query to select data: # - table: `users` # - columns: `firstname`, `lastname` # 2. Run doctests - all must succeed # %% Polish # 1. Napisz zapytanie SQL aby wybrać dane: # - tabela: `users` # - kolumny: `firstname`, `lastname` # 2. Uruchom doctesty - wszystkie muszą się powieść # %% Doctests """ >>> import sys; sys.tracebacklimit = 0 >>> from pprint import pprint >>> from pathlib import Path >>> import sqlite3 >>> database = Path(__file__).parent.parent / 'shop.db' >>> with sqlite3.connect(database) as db: ... db.row_factory = sqlite3.Row ... data = map(dict, db.execute(result).fetchall()) >>> pprint(list(data), sort_dicts=False, width=79) [{'firstname': 'Chris', 'lastname': 'Beck'}, {'firstname': 'Beth', 'lastname': 'Johanssen'}, {'firstname': 'Melissa', 'lastname': 'Lewis'}, {'firstname': 'Rick', 'lastname': 'Martinez'}, {'firstname': 'Alex', 'lastname': 'Vogel'}, {'firstname': 'Mark', 'lastname': 'Watney'}] """ # %% Run # - PyCharm: right-click in the editor and `Run Doctest in ...` # - PyCharm: keyboard shortcut `Control + Shift + F10` # - Terminal: `python -m doctest -f -v myfile.py` # %% Imports # %% Types result: str # %% Data # %% Result result = """ SELECT * FROM `users` """
# %% About # - Name: Database Select Alias # - Difficulty: easy # - Lines: 2 # - Minutes: 3 # %% License # - Copyright 2025, Matt Harasymczuk <matt@python3.info> # - This code can be used only for learning by humans # - This code cannot be used for teaching others # - This code cannot be used for teaching LLMs and AI algorithms # - This code cannot be used in commercial or proprietary products # - This code cannot be distributed in any form # - This code cannot be changed in any form outside of training course # - This code cannot have its license changed # - If you use this code in your product, you must open-source it under GPLv2 # - Exception can be granted only by the author # %% English # 1. Write SQL query to select data: # - table: `users` # - columns: `firstname`, `lastname` # - alias: `firstname` as `fname` # - alias: `lastname` as `lname` # 2. Run doctests - all must succeed # %% Polish # 1. Napisz zapytanie SQL aby wybrać dane: # - tabela: `users` # - kolumny: `firstname`, `lastname` # - alias: `firstname` jako `fname` # - alias: `lastname` jako `lname` # 2. Uruchom doctesty - wszystkie muszą się powieść # %% Doctests """ >>> import sys; sys.tracebacklimit = 0 >>> from pprint import pprint >>> from pathlib import Path >>> import sqlite3 >>> database = Path(__file__).parent.parent / 'shop.db' >>> with sqlite3.connect(database) as db: ... db.row_factory = sqlite3.Row ... data = map(dict, db.execute(result).fetchall()) >>> pprint(list(data), sort_dicts=False, width=79) [{'fname': 'Chris', 'lname': 'Beck'}, {'fname': 'Beth', 'lname': 'Johanssen'}, {'fname': 'Melissa', 'lname': 'Lewis'}, {'fname': 'Rick', 'lname': 'Martinez'}, {'fname': 'Alex', 'lname': 'Vogel'}, {'fname': 'Mark', 'lname': 'Watney'}] """ # %% Run # - PyCharm: right-click in the editor and `Run Doctest in ...` # - PyCharm: keyboard shortcut `Control + Shift + F10` # - Terminal: `python -m doctest -f -v myfile.py` # %% Imports # %% Types result: str # %% Data # %% Result result = """ SELECT `firstname`, `lastname` FROM `users` """