There are a few key limitations in Hive that prevent some regular Metadata Editor
features from working as intended, and will limit the structure of your SQL queries in
Report Designer:
- Outer joins are not supported.
- Each column can only be used once in a SELECT clause. Duplicate columns in
SELECT statements will cause errors.
- Conditional joins can only use the = conditional unless you use a WHERE
clause. Any non-equal conditional in a FROM statement will force Metadata
Editor to use a cartesian join and a WHERE clause conditional to limit it. This is
not much of a limitation, but it will seem unusual to experienced Metadata Editor
users who are accustomed to working with SQL databases.