What it requires. Relation declarations do not follow the documented LHS-first ordering for the constraints that use them.
Why it matters. [doc] "Order of relations matter for constraint evaluation. Specify the relations used in the LHS of the constraints first, followed by those in the RHS" (CML Best Practices). That sentence is the strongest published claim: Salesforce states that ordering matters for constraint evaluation, and no measurements of the cost exist publicly. Detection requires parsing, not grep - build cost noted.
How to fix it. Reorder relation declarations to match constraint LHS-then-RHS usage.
Source. Salesforce CML Best Practices (developer guide)
Is this rule worth checking?
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