enter()#

relationalai.Context
Context.__enter__() -> ContextSelect

Context objects are context managers. Although you can call the .__enter__() method directly, it is typically called by a with statement.

In a with statement, Python calls the context manager’s .__enter__() method before executing the with block. Optionally, you may give the ContextSelect object returned by .__enter__() a name in the as part of the with statement. After the with block executes, the with statement automatically executes the Context.__exit__() method.

Returns#

A ContextSelect object.

Example#

You create rule contexts with Model.rule() and query contexts with Model.query(). The Model.query() context’s .__enter__() method returns a ContextSelect object, typically given the name select, that you use to select query results:

import relationalai as rai

model = rai.Model("people")
Person = model.Type("Person")

# The `with` statement calls the `model.rule()` context's
# `.__enter__()` method automatically. The `ContextSelect` object
# returned by `.__enter__()` is not typically used in a rule.
with model.rule():
    Person.add(name="Fred")

# The `with` statement calls the `model.query()` context's
# `.__enter__()` method and assigns the `ContextSelect`
# object it returns to a Python variable named `select`.
with model.query() as select:
    person = Person()
    response = select(person.name)

print(response.results)
# Output:
#    name
# 0  Fred

Calling select returns the same Context object created by model.query() in the with statement. The results of the query are stored as a pandas DataFrame and are accessible via the Context.results attribute.

See Also#