Coverage for docs_src / tutorial / relationship_attributes / cascade_delete_relationships / tutorial003_py39.py: 100%

1from typing import Optional 9 ctx1jklmnopqr

2 

3from sqlmodel import Field, Relationship, Session, SQLModel, create_engine, select, text 9 ctx1jklmnopqr

4 

5 

6class Team(SQLModel, table=True): 9 ctx1jklmnopqr

7 id: Optional[int] = Field(default=None, primary_key=True) 9 ctx1jklmnopqr

8 name: str = Field(index=True) 9 ctx1jklmnopqr

9 headquarters: str 9 ctx1jklmnopqr

10 

11 heroes: list["Hero"] = Relationship(back_populates="team", passive_deletes="all") 9 ctx1jklmnopqr

12 

13 

14class Hero(SQLModel, table=True): 9 ctx1jklmnopqr

15 id: Optional[int] = Field(default=None, primary_key=True) 9 ctx1jklmnopqr

16 name: str = Field(index=True) 9 ctx1jklmnopqr

17 secret_name: str 9 ctx1jklmnopqr

18 age: Optional[int] = Field(default=None, index=True) 9 ctx1jklmnopqr

19 

20 team_id: Optional[int] = Field( 9 ctx1jklmnopqr

21 default=None, foreign_key="team.id", ondelete="SET NULL" 

22 ) 

23 team: Optional[Team] = Relationship(back_populates="heroes") 9 ctx1jklmnopqr

24 

25 

26sqlite_file_name = "database.db" 9 ctx1jklmnopqr

27sqlite_url = f"sqlite:///{sqlite_file_name}" 9 ctx1jklmnopqr

28 

29engine = create_engine(sqlite_url, echo=True) 9 ctx1jklmnopqr

30 

31 

32def create_db_and_tables(): 9 ctx1jklmnopqr

33 SQLModel.metadata.create_all(engine) 9 ctx1abcdefghi

34 with engine.connect() as connection: 9 ctx1abcdefghi

35 connection.execute(text("PRAGMA foreign_keys=ON")) # for SQLite only 9 ctx1abcdefghi

36 

37 

38def create_heroes(): 9 ctx1jklmnopqr

39 with Session(engine) as session: 9 ctx1abcdefghi

40 team_preventers = Team(name="Preventers", headquarters="Sharp Tower") 9 ctx1abcdefghi

41 team_z_force = Team(name="Z-Force", headquarters="Sister Margaret's Bar") 9 ctx1abcdefghi

42 

43 hero_deadpond = Hero( 9 ctx1abcdefghi

44 name="Deadpond", secret_name="Dive Wilson", team=team_z_force 

45 ) 

46 hero_rusty_man = Hero( 9 ctx1abcdefghi

47 name="Rusty-Man", secret_name="Tommy Sharp", age=48, team=team_preventers 

48 ) 

49 hero_spider_boy = Hero(name="Spider-Boy", secret_name="Pedro Parqueador") 9 ctx1abcdefghi

50 session.add(hero_deadpond) 9 ctx1abcdefghi

51 session.add(hero_rusty_man) 9 ctx1abcdefghi

52 session.add(hero_spider_boy) 9 ctx1abcdefghi

53 session.commit() 9 ctx1abcdefghi

54 

55 session.refresh(hero_deadpond) 9 ctx1abcdefghi

56 session.refresh(hero_rusty_man) 9 ctx1abcdefghi

57 session.refresh(hero_spider_boy) 9 ctx1abcdefghi

58 

59 print("Created hero:", hero_deadpond) 9 ctx1abcdefghi

60 print("Created hero:", hero_rusty_man) 9 ctx1abcdefghi

61 print("Created hero:", hero_spider_boy) 9 ctx1abcdefghi

62 

63 hero_spider_boy.team = team_preventers 9 ctx1abcdefghi

64 session.add(hero_spider_boy) 9 ctx1abcdefghi

65 session.commit() 9 ctx1abcdefghi

66 session.refresh(hero_spider_boy) 9 ctx1abcdefghi

67 print("Updated hero:", hero_spider_boy) 9 ctx1abcdefghi

68 

69 hero_black_lion = Hero(name="Black Lion", secret_name="Trevor Challa", age=35) 9 ctx1abcdefghi

70 hero_sure_e = Hero(name="Princess Sure-E", secret_name="Sure-E") 9 ctx1abcdefghi

71 team_wakaland = Team( 9 ctx1abcdefghi

72 name="Wakaland", 

73 headquarters="Wakaland Capital City", 

74 heroes=[hero_black_lion, hero_sure_e], 

75 ) 

76 session.add(team_wakaland) 9 ctx1abcdefghi

77 session.commit() 9 ctx1abcdefghi

78 session.refresh(team_wakaland) 9 ctx1abcdefghi

79 print("Team Wakaland:", team_wakaland) 9 ctx1abcdefghi

80 

81 

82def delete_team(): 9 ctx1jklmnopqr

83 with Session(engine) as session: 9 ctx1abcdefghi

84 statement = select(Team).where(Team.name == "Wakaland") 9 ctx1abcdefghi

85 team = session.exec(statement).one() 9 ctx1abcdefghi

86 session.delete(team) 9 ctx1abcdefghi

87 session.commit() 9 ctx1abcdefghi

88 print("Deleted team:", team) 9 ctx1abcdefghi

89 

90 

91def select_deleted_heroes(): 9 ctx1jklmnopqr

92 with Session(engine) as session: 9 ctx1abcdefghi

93 statement = select(Hero).where(Hero.name == "Black Lion") 9 ctx1abcdefghi

94 result = session.exec(statement) 9 ctx1abcdefghi

95 hero = result.first() 9 ctx1abcdefghi

96 print("Black Lion has no team:", hero) 9 ctx1abcdefghi

97 

98 statement = select(Hero).where(Hero.name == "Princess Sure-E") 9 ctx1abcdefghi

99 result = session.exec(statement) 9 ctx1abcdefghi

100 hero = result.first() 9 ctx1abcdefghi

101 print("Princess Sure-E has no team:", hero) 9 ctx1abcdefghi

102 

103 

104def main(): 9 ctx1jklmnopqr

105 create_db_and_tables() 9 ctx1abcdefghi

106 create_heroes() 9 ctx1abcdefghi

107 delete_team() 9 ctx1abcdefghi

108 select_deleted_heroes() 9 ctx1abcdefghi

109 

110 

111if __name__ == "__main__": 9 ctx1jklmnopqr

112 main()