Summary
Dremio is not able to parse certain unicode characters. For example, running a query that contains the € character, will produce error messages.
Reported Issue
There are several error messages that have been reported when using certain unsupported characters in a query. For example:
PLAN ERROR: Error during planning the query.
Conversion to relational algebra failed to preserve datatypes
Relevant Versions
All Dremio Versions
Cause
Dremio does not support certain characters, and does not do an automatic conversion.
Steps to Resolve
You can manually convert the characters in your SQL queries by adding "_utf8" as a prefix.
For example:SELECT _utf8'€'will work whereasSELECT '€'fails with the error from above.