DataStateAdd indicates tenant data is being added.

DataStateDrop indicates tenant data is being deleted.

DataStateReady indicates data is ready and SQL servers can access it.

MaxDataState is a sentinel value.

MaxServiceMode is a sentinel value.

ServiceModeExternal says that service is allowed using separate processes.

ServiceModeNode says that no service is allowed.

ServiceModeShared says that service is allowed using shared-process multitenancy on KV nodes.

ServiceModeStopping says that the service was previusly in ServiceModeShared but is in the process of stopping.

TenantDataStateValues facilitates the string -> TenantDataState conversion.

TenantServiceModeValues facilitates the string -> TenantServiceMode conversion.

TenantInfo captures both a ProtoInfo and the SQLInfo columns that go alongside it, sufficient to represent an entire row in system.tenants.

TenantDataState describes the state of a tenant's logical keyspace.

TenantServiceMode describes how tenants can be served to clients.