Filtering Across Multiple Year-Partitioned Tables in Looker/BigQuery

[zdenek_hanzal-1]

We have BigQuery tables partitioned (sharded) by year (table_YYYY) into many tables having same schemas. The tables are huge (terabytes) and numerous(30+) (to build just one) and users do not need to select all the years usually only few of them, sometimes one only.

Users need to filter by year (filtering year dimension or via parameter/filter), potentially selecting multiple years (e.g., 2022, 2023).
I'm looking for the most efficient and maintainable way to achieve this in LookML.
Ideally, if a user selects years "2022,2023," the generated SQL should resemble:

SELECT * FROM table_2022
UNION ALL
SELECT * FROM table_2023

How can we accomplish this dynamic UNION behavior based on the filter selection?

We were playing with liquid parameters and templated filters but looks like with parameters user can only select one year (mono selection).