Added features for Nessie branch management

[lorepas]

Summary

This PR contains code updates that enable branch management for Nessie source code.

Description

The changes made allowed us to specify two new configurations:

• branch: allows you to specify a branch. If used in a materialized application, it creates the PDS on the specified branch (if the branch doesn't exist, it creates it first). If used in a VDS, however, it creates it from the PDS and the specified branch.
• nessie_ref: to be inserted in a materialized application. When present, it creates the new branch from the reference entered; otherwise, if the branch doesn't exist, it is created from main.

Test Results

• Dremio OSS: 25.1.1
• Nessie: 0.105.3
• dbt-dremio: 1.10.0

I performed the following tests with this stack:

• Created a Nessie-type source on Dremio
• Created a tag named "init" from the Dremio interface
• In the dbt project, I created a create_pds.sql file for the PDS to be created on Nessie and a my_first_query.sql file for the VDS to be created from the PDS on a Space in the Staging folder:

{{ config(
object_storage_source="mynessiesource",
materialized="table",
branch="test_1"
) }}

SELECT * FROM Samples."samples.dremio.com"."NYC-taxi-trips.csv"

{{ config(
schema = "Staging",
materialized="view",
branch="test_1"
) }}

select *
from {{ ref('create_pds') }}

• Starting the project with dbt run correctly creates the test_1 branch and creates pds and vds with the correct points to the specified branch.

• If we rerun dbt run without changing anything, it checks whether a table with that name already exists in the branch; if it does, it is deleted and then recreated.

• In create_pds.sql, you can also add the nessie_ref config, specifying a valid reference (for example, the tag created at the beginning):

{{ config(
object_storage_source="mynessiesource",
materialized="table",
branch="test_2",
nessie_ref="init"
) }}

SELECT * FROM Samples."samples.dremio.com"."NYC-taxi-trips.csv"

• This way, the test_2 branch is created starting from the init tag. This can be useful if we want to create PDSs starting from specific tags/branches/commits.
• From Dremio, I see that the test_2 branch is correctly created starting from the tag.
• Without specifying branch or nessie_ref config, the behavior is the usual one.

Changelog

• Added a summary of what this PR accomplishes to CHANGELOG.md

Contributor License Agreement

• Please make sure you have signed our Contributor License Agreement, which enables Dremio to distribute your contribution without restriction.

Related Issue

• [Bug]: Validation of view sql failed. Version context for table nessie.names must be specified using AT SQL syntax #241

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

---

lorenzop seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}