Why should you care?

Every enterprise resource (patient, invoice, SKU) needs full lifecycle operations with correct filters.

See it live — copy this example

Paste into your MeanVerse project (Angular + Express + MongoDB), then run with ng serve / node / mongosh as noted.

// Mongoose CRUD
await Account.create({ tenantId, name: 'Payroll', balanceCents: 0 });
const acct = await Account.findOne({ _id: id, tenantId });
await Account.updateOne({ _id: id, tenantId }, { $set: { name: 'Payroll USD' } });
await Account.deleteOne({ _id: id, tenantId, balanceCents: 0 });

What happened?

• Always include tenantId in filter for SaaS safety.
• updateOne $set changes fields without replacing whole doc.
• deleteOne guards zero balance.

Practice next

1. build CRUD Express routes for one resource.
2. Use lean() on reads for plain JSON performance.
3. Return 404 when matchedCount is 0 on update.
4. Add findOneAndUpdate with returnDocument: 'after'.
5. Implement soft delete middleware excluding deleted docs.

Remember

CRUD maps to Mongo operators and Mongoose. Filters must include tenant scope. Prefer $set updates over full replace.

CRM contact lifecycle

Sales edits lead, archives instead of delete for compliance.

Outcome: CRUD API supports active list and archived audit views.