[thom]

Postgres is capable of doing this with some index types, but generally more slowly than a B-tree index being asked about its leftmost columns:

https://www.postgresql.org/docs/current/indexes-multicolumn....

Also worth noting that for very complex workloads that need to support arbitrary subsets of equality matches over columns, a Bloom filter might work best:

https://www.postgresql.org/docs/current/bloom.html