From 5e30087db4a06c24c103737d4cb7dcdf06da5b24 Mon Sep 17 00:00:00 2001 From: Stefan Majewsky Date: Sun, 12 Apr 2026 17:18:43 +0200 Subject: add Store.SelectOne --- query.go | 92 ---------------------------------------------------------------- 1 file changed, 92 deletions(-) delete mode 100644 query.go (limited to 'query.go') diff --git a/query.go b/query.go deleted file mode 100644 index fd80f56..0000000 --- a/query.go +++ /dev/null @@ -1,92 +0,0 @@ -// SPDX-FileCopyrightText: 2026 Stefan Majewsky -// SPDX-License-Identifier: Apache-2.0 - -package oblast - -import ( - "database/sql" - "fmt" - "reflect" - - "go.xyrillian.de/oblast/internal" -) - -func (s Store[R]) Select(db Handle, query string, args ...any) (result []R, returnedError error) { - // NOTE: This function body should be as short as possible to reduce the binary size after monomorphization. - // Any expression that does not depend on type R should be factored out into a reusable function. - - rows, indexes, err := startQuery(db, s.plan, query, args...) - if err != nil { - return nil, err - } - defer func() { - returnedError = mergeRowsCloseError(returnedError, rows.Close()) - }() - - slots := make([]any, len(indexes)) - for rows.Next() { - var target R - err = collectRow(rows, reflect.ValueOf(&target).Elem(), slots, indexes) - if err != nil { - return nil, err - } - result = append(result, target) - } - - return result, nil -} - -func startQuery(db Handle, plan internal.Plan, query string, args ...any) (rows *sql.Rows, indexes [][]int, err error) { - rows, err = db.Query(query, args...) - if err != nil { - return nil, nil, fmt.Errorf("during Query(): %w", err) - } - defer func() { - if err != nil { - closeErr := rows.Close() - if closeErr != nil { - err = fmt.Errorf("%w (additional error during rows.Close(): %s)", err, closeErr.Error()) - } - } - }() - - columnNames, err := rows.Columns() - if err != nil { - return nil, nil, fmt.Errorf("during rows.Columns(): %w", err) - } - indexes = make([][]int, len(columnNames)) - for idx, columnName := range columnNames { - var ok bool - indexes[idx], ok = plan.IndexByColumnName[columnName] - if !ok { - return nil, nil, fmt.Errorf( - "result has column %q in position %d, but no field in record type has `db:%[1]q`", - columnName, idx, - ) - } - } - - return rows, indexes, nil -} - -func collectRow(rows *sql.Rows, v reflect.Value, slots []any, indexes [][]int) error { - for idx, index := range indexes { - slots[idx] = v.FieldByIndex(index).Addr().Interface() - } - err := rows.Scan(slots...) - if err != nil { - return fmt.Errorf("during rows.Scan(): %w", err) - } - return nil -} - -func mergeRowsCloseError(err, closeErr error) error { - switch { - case closeErr == nil: - return err - case err == nil: - return fmt.Errorf("during rows.Close(): %w", closeErr) - default: - return fmt.Errorf("%w (additional error during rows.Close(): %s)", err, closeErr.Error()) - } -} -- cgit v1.2.3