Constraints

Subtopics

EdgeQL Tutorial

Constraints

Typically constraints are places on properties. Constraints prevent undesirable data from being inserted. They also stop any updates that would violate the constraint condition. An example of this is an exclusive constraint on User's email:

Input

DESCRIBE OBJECT User AS SDL;

DESCRIBE OBJECT User AS SDL;

Run

Output

Press the 'Run' button to evaluate the input

Let's try creating a new user that could clash with an existing one:

Input

INSERT User {
    name := 'Clone',
    email := 'alice@tutorial.com'
};

INSERT User {
    name := 'Clone',
    email := 'alice@tutorial.com'
};

Run

Output

Press the 'Run' button to evaluate the input

Feel free to experiment with the above command, perhaps to make an UPDATE that would violate the exclusive email constraint.

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