LEARN. PRACTICE. GROW.Concept and mechanism
Relationship choices should reflect data lifecycle. For custom objects, master-detail creates dependency and can delete details when the master is deleted. Lookup supports evaluating a relationship with greater independence. A master roll-up aggregate uses an appropriate relationship but does not justify ignoring detail-retention requirements.
Guided application
First design entities, cardinality, ownership, and retention. Then choose fields and calculations, identify deletion effects, and define how existing data will migrate. Record types help distinguish processes, picklist values, and layouts on one object. Security remains the responsibility of access controls. Saving a Lightning page also requires completing availability setup for the intended audience. Use a small operation matrix to review the model: create a master, add details, change an amount, remove a detail, and attempt to delete the master. For each operation, write down which records and totals should remain. Comparing that expected result with relationship semantics exposes conflicts before thousands of records exist. Also include who authorizes each operation and how a denied attempt will be handled. This makes the design review reproducible.
An operational review has several evidence records that must survive archiving or deletion of the review. The prototype uses master-detail solely to obtain a sum. Before delivery, the team reviews dependency, the deletion process, and an alternative for calculating the total. A mandatory screen field does not resolve that structural retention conflict.
Common pitfalls
Do not use record types as a confidentiality boundary. An editable layout does not override read-only field security. In a validation rule, a true formula identifies the invalid condition; it does not mean the value was accepted.
Related topics: Effective access and user lifecycle · Leads, campaigns, and commercial follow-up · Cases, queues, and operational escalation
Validate the model through creation, updates, deletion, and retention before judging it only by form appearance.
Reference: Object Relationships · Platform Administrator guide Summer 25