These objects doesn’t support DML operations from Apex, but it supports SOQL(Querying)
- AccountTerritoryAssignmentRule
- AccountTerritoryAssignmentRuleItem
- ApexComponent
- ApexPage
- BusinessHours
- BusinessProcess
- CategoryNode
- CurrencyType
- DatedConversionRate
- ProcessInstance
- Profile
- RecordType
- SelfServiceUser
- StaticResource
- UserAccountTeamMember
- UserTerritory
- WebLink