postgres connector for prestodb not recognizing UUIDs

[apatnaik14]

Hi Team,

My underlying database is that of postgres and a majority of my primary keys are UUIDs. When I access my database from my presto setup, I am unable to see the UUID columns in the describe or perform joins or queries on them.

I feel this is a known issue and I am sorry for raising a duplicate ticket if already one exists. I was hoping to see if this is something that will be added to the connector/prestodb later on in future releases.

Workaround option I thought of -

Creating a VIEW object in postgres with typecast of UUIDs to 'varchar'. But as always its best not to join on varchars, so I'd like to avoid the approach if possible.

Please feel free to let me know if I am missing anything. Please find below the details of presto I am using

presto-server-0.157
Postgres Version - "PostgreSQL 9.6.9 on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 7.2.0-8ubuntu3.2) 7.2.0, 64-bit"

Thanks,
A

[findepi]

Creating a VIEW object in postgres with typecast of UUIDs to 'varchar'. But as always its best not to join on varchars, so I'd like to avoid the approach if possible.

The workaround isn't as bad as it sounds.
Postgres UUIDs will be modelled probably as varchars anyway, since Presto doesn't have dedicated UUID type.

If you'd like to implement this

• the types are mapped in BaseJdbcClient.toPrestoType (needs postgres-specific override)
• the tests are in TestPostgreSqlTypeMapping