initial MVP for oblast.Select()

1 files changed, 131 insertions, 0 deletions

diff --git a/benchmark/benchmark_test.go b/benchmark/benchmark_test.go
new file mode 100644
index 0000000..c08361e
--- /dev/null
+++ b/benchmark/benchmark_test.go
@@ -0,0 +1,131 @@
+// SPDX-FileCopyrightText: 2026 Stefan Majewsky <majewsky@gmx.net>
+// SPDX-License-Identifier: Apache-2.0
+
+package main_test
+
+import (
+	"crypto/sha256"
+	"database/sql"
+	"fmt"
+	"strconv"
+	"testing"
+
+	"github.com/go-gorp/gorp/v3"
+	_ "github.com/mattn/go-sqlite3"
+	"go.xyrillian.de/oblast"
+)
+
+func BenchmarkSelect(b *testing.B) {
+	const (
+		totalRecordCount    = 10000
+		selectedRecordCount = 1
+	)
+
+	db, err := sql.Open("sqlite3", "file:foobar?mode=memory&cache=shared")
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	// fill in some random-looking, but deterministic data
+	_, err = db.Exec(`CREATE TABLE entries (id INTEGER, message TEXT)`)
+	if err != nil {
+		b.Fatal(err)
+	}
+	stmt, err := db.Prepare(`INSERT INTO entries (id, message) VALUES (?, ?)`)
+	if err != nil {
+		b.Fatal(err)
+	}
+	for idx := range totalRecordCount {
+		buf := sha256.Sum256([]byte(strconv.Itoa(idx)))
+		_, err = stmt.Exec(idx, fmt.Sprintf("sha256:%x", buf[:]))
+		if err != nil {
+			b.Fatal(err)
+		}
+	}
+	err = stmt.Close()
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	// prepare the functions that will be benched
+	odb := oblast.NewDB(db, oblast.SqliteDialect())
+	gdb := gorp.DbMap{Db: db, Dialect: gorp.SqliteDialect{}}
+	type record struct {
+		ID      int    `db:"id"`
+		Message string `db:"message"`
+	}
+	query := `SELECT * FROM entries WHERE id < ` + strconv.Itoa(selectedRecordCount)
+
+	selectWithOblast := func(b *testing.B) {
+		records, err := oblast.Select[record](b.Context(), odb, query)
+		if err != nil {
+			b.Error(err)
+		}
+		if len(records) != selectedRecordCount {
+			b.Errorf("expected %d, but got %d records", selectedRecordCount, len(records))
+		}
+	}
+
+	selectWithGorp := func(b *testing.B) {
+		var records []record
+		_, err := gdb.Select(&records, query)
+		if err != nil {
+			b.Error(err)
+		}
+		if len(records) != selectedRecordCount {
+			b.Errorf("expected %d, but got %d records", selectedRecordCount, len(records))
+		}
+	}
+
+	selectWithSqlite := func(b *testing.B) {
+		var count int64
+		rows, err := db.Query(query)
+		if err != nil {
+			b.Error(err)
+		}
+		var (
+			id      int64
+			message string
+		)
+		for rows.Next() {
+			err := rows.Scan(&id, &message)
+			if err != nil {
+				b.Error(err)
+			}
+			if id != 20000 && message != "" { // always true; ensures that values are not optimized away
+				count++
+			}
+		}
+		err = rows.Close()
+		if err != nil {
+			b.Error(err)
+		}
+		if count != selectedRecordCount {
+			b.Errorf("expected %d, but got %d records", selectedRecordCount, count)
+		}
+	}
+
+	// run once to prewarm caches
+	selectWithOblast(b)
+	selectWithGorp(b)
+	if b.Failed() {
+		b.FailNow()
+	}
+
+	// run actual benchmark
+	b.Run("via Gorp", func(b *testing.B) {
+		for range b.N {
+			selectWithGorp(b)
+		}
+	})
+	b.Run("via Oblast", func(b *testing.B) {
+		for range b.N {
+			selectWithOblast(b)
+		}
+	})
+	b.Run("just SQLite", func(b *testing.B) {
+		for range b.N {
+			selectWithSqlite(b)
+		}
+	})
+}