# Create Data with Many-to-Many Relationships Let's continue from where we left and create some data. We'll create data for this same **many-to-many** relationship with a link table: many-to-many table relationships We'll continue from where we left off with the previous code. /// details | 👀 Full file preview //// tab | Python 3.10+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py310.py!} ``` //// //// tab | Python 3.9+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py39.py!} ``` //// //// tab | Python 3.7+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001.py!} ``` //// /// ## Create Heroes As we have done before, we'll create a function `create_heroes()` and we'll create some teams and heroes in it: //// tab | Python 3.10+ ```Python hl_lines="11" # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001_py310.py[ln:36-54]!} # Code below omitted 👇 ``` //// //// tab | Python 3.9+ ```Python hl_lines="11" # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001_py39.py[ln:42-60]!} # Code below omitted 👇 ``` //// //// tab | Python 3.7+ ```Python hl_lines="11" # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001.py[ln:42-60]!} # Code below omitted 👇 ``` //// /// details | 👀 Full file preview //// tab | Python 3.10+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py310.py!} ``` //// //// tab | Python 3.9+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py39.py!} ``` //// //// tab | Python 3.7+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001.py!} ``` //// /// This is very similar to what we have done before. We create a couple of teams, and then three heroes. The only new detail is that instead of using an argument `team` we now use `teams`, because that is the name of the new **relationship attribute**. And more importantly, we pass a **list of teams** (even if it contains a single team). See how **Deadpond** now belongs to the two teams? ## Commit, Refresh, and Print Now let's do as we have done before, `commit` the **session**, `refresh` the data, and print it: //// tab | Python 3.10+ ```Python hl_lines="22-25 27-29 31-36" # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001_py310.py[ln:36-69]!} # Code below omitted 👇 ``` //// //// tab | Python 3.9+ ```Python hl_lines="22-25 27-29 31-36" # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001_py39.py[ln:42-75]!} # Code below omitted 👇 ``` //// //// tab | Python 3.7+ ```Python hl_lines="22-25 27-29 31-36" # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001.py[ln:42-75]!} # Code below omitted 👇 ``` //// /// details | 👀 Full file preview //// tab | Python 3.10+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py310.py!} ``` //// //// tab | Python 3.9+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py39.py!} ``` //// //// tab | Python 3.7+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001.py!} ``` //// /// ## Add to Main As before, add the `create_heroes()` function to the `main()` function to make sure it is called when running this program from the command line: //// tab | Python 3.10+ ```Python # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001_py310.py[ln:72-74]!} # Code below omitted 👇 ``` //// //// tab | Python 3.9+ ```Python # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001_py39.py[ln:78-80]!} # Code below omitted 👇 ``` //// //// tab | Python 3.7+ ```Python # Code above omitted 👆 {!./docs_src/tutorial/many_to_many/tutorial001.py[ln:78-80]!} # Code below omitted 👇 ``` //// /// details | 👀 Full file preview //// tab | Python 3.10+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py310.py!} ``` //// //// tab | Python 3.9+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001_py39.py!} ``` //// //// tab | Python 3.7+ ```Python {!./docs_src/tutorial/many_to_many/tutorial001.py!} ``` //// /// ## Run the Program If we run the program from the command line, it would output:
```console $ python app.py // Previous output omitted 🙈 // Automatically start a new transaction INFO Engine BEGIN (implicit) // Insert the hero data first INFO Engine INSERT INTO hero (name, secret_name, age) VALUES (?, ?, ?) INFO Engine [generated in 0.00041s] ('Deadpond', 'Dive Wilson', None) INFO Engine INSERT INTO hero (name, secret_name, age) VALUES (?, ?, ?) INFO Engine [cached since 0.001942s ago] ('Rusty-Man', 'Tommy Sharp', 48) INFO Engine INSERT INTO hero (name, secret_name, age) VALUES (?, ?, ?) INFO Engine [cached since 0.002541s ago] ('Spider-Boy', 'Pedro Parqueador', None) // Insert the team data second INFO Engine INSERT INTO team (name, headquarters) VALUES (?, ?) INFO Engine [generated in 0.00037s] ('Z-Force', 'Sister Margaret's Bar') INFO Engine INSERT INTO team (name, headquarters) VALUES (?, ?) INFO Engine [cached since 0.001239s ago] ('Preventers', 'Sharp Tower') // Insert the link data last, to be able to re-use the created IDs INFO Engine INSERT INTO heroteamlink (team_id, hero_id) VALUES (?, ?) INFO Engine [generated in 0.00026s] ((2, 3), (1, 1), (2, 1), (2, 2)) // Commit and save the data in the database INFO Engine COMMIT // Automatically start a new transaction INFO Engine BEGIN (implicit) // Refresh the data INFO Engine SELECT hero.id, hero.name, hero.secret_name, hero.age FROM hero WHERE hero.id = ? INFO Engine [generated in 0.00019s] (1,) INFO Engine SELECT hero.id, hero.name, hero.secret_name, hero.age FROM hero WHERE hero.id = ? INFO Engine [cached since 0.001959s ago] (2,) INFO Engine SELECT hero.id, hero.name, hero.secret_name, hero.age FROM hero WHERE hero.id = ? INFO Engine [cached since 0.003215s ago] (3,) // Print Deadpond Deadpond: name='Deadpond' age=None id=1 secret_name='Dive Wilson' // Accessing the .team attribute triggers a refresh INFO Engine SELECT team.id AS team_id, team.name AS team_name, team.headquarters AS team_headquarters FROM team, heroteamlink WHERE ? = heroteamlink.hero_id AND team.id = heroteamlink.team_id INFO Engine [generated in 0.00025s] (1,) // Print Deadpond's teams, 2 teams! 🎉 Deadpond teams: [Team(id=1, name='Z-Force', headquarters='Sister Margaret's Bar'), Team(id=2, name='Preventers', headquarters='Sharp Tower')] // Print Rusty-Man Rusty-Man: name='Rusty-Man' age=48 id=2 secret_name='Tommy Sharp' // Accessing the .team attribute triggers a refresh INFO Engine SELECT team.id AS team_id, team.name AS team_name, team.headquarters AS team_headquarters FROM team, heroteamlink WHERE ? = heroteamlink.hero_id AND team.id = heroteamlink.team_id INFO Engine [cached since 0.001716s ago] (2,) // Print Rusty-Man teams, just one, but still a list Rusty-Man Teams: [Team(id=2, name='Preventers', headquarters='Sharp Tower')] // Print Spider-Boy Spider-Boy: name='Spider-Boy' age=None id=3 secret_name='Pedro Parqueador' // Accessing the .team attribute triggers a refresh INFO Engine SELECT team.id AS team_id, team.name AS team_name, team.headquarters AS team_headquarters FROM team, heroteamlink WHERE ? = heroteamlink.hero_id AND team.id = heroteamlink.team_id INFO Engine [cached since 0.002739s ago] (3,) // Print Spider-Boy's teams, just one, but still a list Spider-Boy Teams: [Team(id=2, name='Preventers', headquarters='Sharp Tower')] // Automatic roll back any previous automatic transaction, at the end of the with block INFO Engine ROLLBACK ```
## Recap After setting up the model link, using it with **relationship attributes** is fairly straightforward, just Python objects. ✨