Feat(optimizer): improve type annotation for nested types

[georgesittas]

Fixes #2060

Reference: https://www.postgresql.org/docs/9.1/functions-array.html

[eric-zhu]

@georgesittas Thank you so much for the quick fix. It works for both array_agg() and filter now. 👍

Could you add support of array_cat() for postgres please? Following are the schema and sql. Thanks a lot.

schema = {
    "order": {
        "item_group1": "text[]",
        "item_group2": "text[]",
    }
}

# item_group1: ARRAY<TEXT>
# item_group2: ARRAY<TEXT>
sql = """
    select order.item_group1, order.item_group2 from order
"""

# test: UNKNOWN
sql = """
    select array_cat(order.item_group1, order.item_group2) as test from order
"""

[georgesittas]

Sure, will add that too

[georgesittas]

@eric-zhu added both ARRAY and ARRAY_CAT.

Feel free to use this PR as an example and add annotation logic for other functions that you need in the future.

[eric-zhu]

Verified it works. Thanks a lot and really appreciate it. 👍