Validate sorting and pagination

Use sgl.sortable when callers should choose a sort column from a fixed set. Accept the generated choices at the application boundary instead of concatenating request text into SQL.

Declare the allowed sort columns

List the columns callers may use in the query's sortable directive:

-- sgl.query(ListEntries, many)
-- sgl.sortable(order_by, [boat, crew, finish_seconds])
SELECT id, boat, crew, finish_seconds FROM entries

Run sgl vet and sgl generate. The method receives a Params struct with an ordering choice and direction, and the generated package supplies constants such as ListEntriesOrderByCrew and OrderDesc.

Map request values to generated choices

Translate your API's accepted values to those constants, then call the method. To list the largest crews first:

rows, err := queries.ListEntries(ctx, store.ListEntriesParams{
    OrderBy: store.ListEntriesOrderByCrew,
    OrderByDirection: store.OrderDesc,
})

Check err before using rows. The tested caller exercises these constants and shows each resulting order.

Validate unknown request values yourself if the application should reject them. The sortable helper omits an invalid column without returning an error; an invalid direction is dropped while the column remains. A runtime builder reports invalid ordering input instead.

Add pagination without losing a stable order

Add named LIMIT and OFFSET parameters as the pagination guide shows. Choose a deterministic ordering for paged results; a size cap does not resolve ties.

The sortable choice replaces the query's top-level ORDER BY. Do not put a SQL parameter inside that original ordering, since it would lose its bind when replaced (Q057). See the directive reference for the complete sortable contract.

The working example includes connection setup and tests. From the repository root, run:

cd examples/sqlite/012_sortable
go test .