Which issue does this PR close?

SQLite does not support defining column aliases as part of alias table definition, for example

SELECT "customers2"."c_name2" FROM
(
	SELECT "customer"."c_name", "customer"."c_address"  FROM "customer"
) AS "customers2"("c_name2", "c_address2")

Must be rewritten as shown below so it can be executed on SQLite.

SELECT "customers2"."c_name2" FROM
(
	SELECT "customer"."c_name" as "c_name2", "customer"."c_address" as "c_address2"  FROM "customer"
) AS "customers2"

PRs address this issue by adding an option for unparser to specify column aliases as part of internal query projection instead of outer table alias definition.

TPC-H Q13 is an example of where such aliasing is used.

select
    c_count,
    count(*) as custdist
from
    (
        select
            c_custkey,
            count(o_orderkey)
        from
            customer left outer join orders on
                        c_custkey = o_custkey
                    and o_comment not like '%special%requests%'
        group by
            c_custkey
    ) as c_orders (c_custkey, c_count)
group by
    c_count
order by
    custdist desc,
    c_count desc;

Rationale for this change

PR introduces supports_column_alias_in_table_alias parameter to control desired behavior and adds logic to produce the right SQL for SQLite dialect.

The logic is applied only if column aliases are provided in the table alias definition and supports_column_alias_in_table_alias is set to false (not supported).

What changes are included in this PR?

See above

Are these changes tested?

Tested manually and added unit tests.

Are there any user-facing changes?

PR introduces new dialect parameter supports_column_alias_in_table_alias that can be used to control the behavior of column aliasing in table aliasing.