Add support for ORDER BY ALL

[PokIsemaine]

Add support for ORDER BY ALL

SELECT *
FROM addresses
ORDER BY ALL;

https://duckdb.org/docs/sql/query_syntax/orderby.html#order-by-all-examples
https://clickhouse.com/docs/en/sql-reference/statements/select/order-by

[iffyio]

Suggested change

	let order_by = if self.parse_keyword(Keyword::ALL) {
	if !self.dialect.supports_order_by_all() {
	return parser_err!(
	"ALL is not supported in ORDER BY",
	self.peek_token().span.start
	);
	}
	let order_by = if self.dialect.supports_order_by_all() && self.parse_keyword(Keyword::ALL) {

can we maybe add a test case for this? that other dialects can successfully parse ORDER BY all

[PokIsemaine]

If an unsupported dialect uses ORDER BY ALL, should we return parser_err or an OrderByKind::Expressions type OrderBy with its expr as ALL?

[iffyio]

Yeah the latter, if an unsupporting dialect sees the query ORDER BY ALL it implies that there's a column/variable in scope called ALL i.e all is an identifier so it'll indeed be correct to parse it as an expression

[iffyio]

Suggested change

	pub fn parse_order_by_all(&mut self) -> Result<OrderByAll, ParserError> {
	fn parse_order_by_all(&mut self) -> Result<OrderByAll, ParserError> {

[iffyio]

can we update parse_order_by_expr to use this helper? since it shares this code so that we avoid keeping both copies in sync

[PokIsemaine]

You are right, this change is better. I plan to first change pub fn parse_order_by_all to fn parse_order_by_options and then reuse it in parse_order_by_expr.

[iffyio]

we can move this outside the match statement and write it unconditionally, representation wise its not tied to kind so it would be confusing to display interpolate conditionally on the kind.

[iffyio]

Suggested change

	// See DuckDB <https://duckdb.org/docs/sql/query_syntax/orderby.html#order-by-all-examples>
	/// See DuckDB <https://duckdb.org/docs/sql/query_syntax/orderby.html#order-by-all-examples>

[PokIsemaine]

I am not very familiar with Rust yet, and I want to know if there are any tools that can automatically unify the comment format of a project, because I saw both // and /// in the same file, which is a bit confusing. Or does this project have any relevant specification documents?

[iffyio]

You're right, we don't run any lint for this in the project unfortunattely so there are discrepancies in the codebase. Ideally especially for public functions, in order for the comment to show up in the documentation /// is required, whereas // is a internal-only code comment