No AS requirements for nested SELECT queries

[xzdandy]

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Description

Right now for nested SELECT queries, the rename AS is required in the query. For example,

SELECT price FROM (SELECT price FROM home_sales) AS T;

The following query will not work:

SELECT price FROM (SELECT price FROM home_sales);

We'd like to add the support for nested SELECT queries without AS to simplify the queries that user wrote.

Use case

No response

Are you willing to submit a PR?

• Yes I'd like to help by submitting a PR!

[gaurav274]

https://www.postgresql.org/docs/7.3/queries-table-expressions.html#QUERIES-SUBQUERIES - PostgreSQL has a similar behavior. We can skip it.

I can make the AS keyword optional, but it makes it easier if we specify the alias_name.

[xzdandy]

Sounds good. Let's keep it consistent with PostgreSQL.