What are the key Database namespace methods developers use beyond basic DML?

Key Database namespace methods: Database.insert(records, allOrNone): Partial success when allOrNone=false. Returns List<Database.SaveResult>. Database.upsert(records, externalIdField, allOrNone): Returns List<Database.UpsertResult> with isCreated() to distinguish insert vs update. Database.delete(records, allOrNone). Database.emptyRecycleBin(records): Hard delete records without Data Loader. Database.convertLead(convertLeadRequest): Convert leads programmatically with full control over mapping. Database.merge(masterRecord, duplicates): Merge up to 3 records. Database.setSavepoint() / Database.rollback(savepoint): Manual transaction savepoints — roll back to a specific point in the transaction if subsequent operations fail. Savepoints do not work across async boundaries.