What does anchor error `2003` mean

Question

What does the error for A raw constraint was violated mean?

    errorCode: { code: 'ConstraintRaw', number: 2003 },
    errorMessage: 'A raw constraint was violated',

Answer 1

These are the types of constraints defined using this syntax #[account(constraint = <expr>)].

From the anchor documentation:

Constraint that checks whether the given expression evaluates to true.
Use this when no other constraint fits your use case.

Example:


#[account(constraint = one.keys[0].age == two.apple.age)]
pub one: Account<'info, MyData>,
pub two: Account<'info, OtherData>