Objects, fields, relationships and the lookup-versus-master-detail decision

Field type, length and picklist strategy are the decisions people regret. Each one here is taught with its migration cost attached.

1. VideoThe field types, and the three you will misuse6 min
2. VideoPicklist, global value set, or lookup to a custom objectA picklist that a business user needs to add values to weekly is a lookup wearing a costume. Decide by who owns the list.Preview7 min
3. ReadingText versus a controlled list: the migration you can avoid6 min
4. VideoField length, and the ceiling you hit two years later7 min
5. VideoDefault values, and the field that trained everyone to ignore it6 min
6. LabLab: pick the right field type for six real requirements6 min

What a formula field can do, and the three things it cannot, taught before you rely on one somewhere load bearing.

1. VideoFormula fields: what they can do, and the three things they cannot7 min
2. VideoCross-object formulas, and how far up the tree they can reach6 min
3. ReadingValidation rules, and where they belong versus a Flow7 min
4. VideoThe formula field whose help text undersold what it didHelp text is a claim, not a guarantee. A field marked informational can still be the thing every other automation depends on.6 min
5. VideoBlank versus zero, and the formula that got it wrong7 min
6. LabLab: write three formula fields a real report will need6 min

The heart of the course. A master-detail relationship buys you rollups and inherited sharing, and costs you cascade delete and restricted reparenting.

1. VideoLookup versus master-detail, stated as a tradeMaster-detail gives native rollup summaries and inherited sharing. It also deletes children with the parent and restricts reparenting.6 min
2. VideoWhat master-detail buys you: rollups and inherited sharing7 min
3. VideoWhat master-detail costs you: cascade delete and restricted reparenting6 min
4. ReadingHierarchical relationships and self-lookups7 min
5. VideoChanging a lookup to master-detail after the fact, and why you rarely can6 min
6. LabLab: model a quoting process end to end7 min

A many-to-many relationship needs a junction object with its own fields, not two bare lookups bolted together.

1. VideoJunction objects, and the duplicate nobody expected6 min
2. VideoA junction object with its own fields, not two bare lookups6 min
3. ReadingMany-to-many reporting, and the report type it needs7 min
4. VideoSharing through a junction: whose access actually wins6 min
5. VideoDeleting one side of a junction, and what happens to the count7 min
6. LabLab: build a junction object and prove the count is right6 min

Rollup summary fields exist only on the master-detail parent. On a lookup they are simply not offered, and that is the whole story.

1. VideoWhy your rollup summary field is greyed outRollup summary fields exist only on the master-detail parent, never on a lookup. On a lookup they are simply not offered, and that is the whole story.7 min
2. VideoMost parent-child links in a real org are lookups, not master-detail6 min
3. ReadingReporting your way to a total without a rollup at all6 min
4. VideoRoll-up summary fields on master-detail: count, sum, min, max7 min
5. VideoThe rollup you cannot build declaratively at all6 min
6. LabLab: find every lookup relationship in an org that wants a rollup7 min

The three connected facts about rollups, in order: most links are lookups, so native rollups are impossible, so you need a tool, and that tool needs a backfill.

1. VideoDeclarative rollup tools, and how they actually recalculateRealtime mode fires on record change. A no-op save does not change anything, so it fires nothing, and your historical totals stay wrong.6 min
2. VideoRealtime mode, and the no-op save that fires nothing6 min
3. ReadingScheduled recalculation, and when you actually need it7 min
4. VideoPurchase order totals wrong on 16 of 79 records, and what fixed itOne purchase order header disagreed with the sum of its own lines. All 79 records were backfilled to zero mismatches.6 min
5. VideoChange request totals empty on 143 records, and the same fix twice7 min
6. LabLab: install a rollup tool, define a rollup, run the backfill, verify the number6 min

The skill that pays for the rest of the course: opening a schema someone else built and reconstructing the decision behind it.

1. VideoReading an existing custom object, and why it was built that way7 min
2. VideoThe three connected facts about rollups, said back to you in one minute6 min
3. ReadingA field inventory: what to record before you touch a schema7 min
4. LabLab: reverse-engineer a custom object’s design decisionsThe capstone lab. Given an unfamiliar custom object, write down every relationship, field type and rollup decision and defend each one.31 min
5. VideoSigns a custom object is about to need a rebuild6 min
6. QuizCheck: objects, fields and relationships12 min