Table Statistics

Table statistics are provided to the query planner by connectors. Currently, the only connector that supports statistics is the Hive Connector.

Statistics are exposed to the query planner by a table layout. A table layout represents a subset of a table’s data and contains information about the organizational properties of that data (like sort order and bucketing).

The number of table layouts available for a table and the details of those table layouts are specific to each connector. Using the Hive connector as an example:

• Non-partitioned tables have just one table layout representing all data in the table

Available Statistics

The following statistics are available in Presto:

The set of statistics available for a particular query depends on the connector being used and can also vary by table or even by table layout. For example, the Hive connector does not currently provide statistics on data size.