BYTES is when an array of bytes is used.

UINT64 is when uint64 value is used.

UNSET is the default value, when range-based sharding is not used.

BACKUP is the type a server goes to when taking a backup.

DRAINED is the type a server goes into when used by Vitess tools to perform an offline action.

EXPERIMENTAL is like SPARE, except it can serve queries.

MASTER is the master server for the shard.

RDONLY (old name) / BATCH (new name) is used to serve traffic for long-running jobs.

REPLICA is a slave type.

RESTORE is the type a server uses when restoring a backup, at startup time.

SPARE is a type of servers that cannot serve queries, but is available in case an extra server is needed.

UNKNOWN is not a valid value.

CellInfo contains information about a cell.

KeyRange describes a range of sharding keys, when range-based sharding is used.

A Keyspace contains data about a keyspace.

ServedFrom indicates a relationship between a TabletType and the keyspace name that's serving it.

A Shard contains data about a subset of the data whithin a keyspace.

ServedType is an entry in the served_types.

SourceShard represents a data source for filtered replication accross shards.

TabletControl controls tablet's behavior.

ShardReference is used as a pointer from a SrvKeyspace to a Shard.

ShardReplication describes the MySQL replication relationships whithin a cell.

Node describes a tablet instance within the cell.

SrvKeyspace is a rollup node for the keyspace itself.

ServedFrom indicates a relationship between a TabletType and the keyspace name that's serving it.

Tablet represents information about a running instance of vttablet.

TabletAlias is a globally unique tablet identifier.

KeyspaceIdType describes the type of the sharding key for a range-based sharded keyspace.

TabletType represents the type of a given tablet.