The following limitations affect the use of Presto connectors with Teradata QueryGrid:
- Foreign function execution
- Use of Presto is limited to queries that can be performed in memory, so some queries may not be able to run in Presto that would run in Hive.
Transaction semantics between systems is not supported.
After data has been exported and committed to a remote system, any subsequent errors or aborts on the local system do not roll back the remote request.
- Presto does not support roles and access control unless Sentry is enabled.
- Teradata QueryGrid does not support TimeWithTimeZone and TimestampWithTimeZone data types with Presto connectors.
- When using the Explain command with a Presto initiator connector, remote query and execution plan data is not returned.
- The default for Timestamp precision is three (3); Teradata QueryGrid truncates data with more than three decimal places.
- When using Predicate pushdowns, Array, Time, TimeWithTimeZone, Timestamp, and TimestampWithTimeZone data types are not pushed down.
- Date literals used in WHERE clauses are not converted to the time zone of the remote system if the remote system time zone is different from the initiator system time zone.
- UTF-16 supplementary characters exceeding more than 2 bytes in a table cause data truncation.