7.9.10. SQL-10 — `_order_by` and `_order_by_descending`

_order_by(key) adds an ORDER BY clause. The key shape decides what the macro emits:

Key shape	Emitted SQL
`_.Field`	`ORDER BY "Field" ASC`
`(_.k1, _.k2, ...)`	`ORDER BY "k1" ASC, "k2" ASC, ...`
`_order_by_descending(_.Field)`	`ORDER BY "Field" DESC`

7.9.10.1. Single-column order

let by_price <- _sql(db |> select_from(type<Car>)
                       |> _order_by(_.Price))
// SELECT "Id", "Name", "Price" FROM "Cars" ORDER BY "Price" ASC

_order_by_descending flips the direction:

let by_price_desc <- _sql(db |> select_from(type<Car>)
                            |> _order_by_descending(_.Price))
// ... ORDER BY "Price" DESC

7.9.10.2. Multi-column tuple key

A tuple-shaped key emits each tuple field as its own ORDER BY column. Useful for primary-and-tie-breaker ordering:

let by_price_then_name <- _sql(db |> select_from(type<Car>)
                                 |> _order_by((_.Price, _.Name)))
// ... ORDER BY "Price" ASC, "Name" ASC

If two rows tie on Price, the second column breaks the tie.

7.9.10.3. Mixed ASC/DESC

A single _order_by step emits all columns in the same direction. Mixed ASC/DESC across columns (e.g. ORDER BY a ASC, b DESC) is out of chunk-4 scope. Until a marker syntax lands, drop down to the raw-SQL escape hatch (query_one / query_scalar / exec) when you need it.

7.9.10.4. Composes with `_where` and `take`

_order_by is just another chain stage — it composes with filter, project, paginate, and aggregate operators in the natural SQL order:

let cheap_top3 <- _sql(db |> select_from(type<Car>)
                         |> _where(_.Price > 50)
                         |> _order_by(_.Price)
                         |> take(3))
// ... WHERE "Price" > ? ORDER BY "Price" ASC LIMIT ?

Note the SQL clause order: WHERE first, ORDER BY next, LIMIT last — same as the chain order.

7.9.10.5. Stable pagination

LIMIT/OFFSET without ORDER BY is non-deterministic — SQLite is free to return rows in any order. Pair take/skip with _order_by whenever you actually care about page boundaries. See SQL-11 — take and skip: Paging.

7.9.10. SQL-10 — _order_by and _order_by_descending