start simple examples

examples/simple-go/demo.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"bytes"
+	"database/sql"
+	"encoding/binary"
+	"fmt"
+	"log"
+
+	sqlite_vec "github.com/asg017/sqlite-vec/bindings/go/cgo"
+	_ "github.com/mattn/go-sqlite3"
+)
+
+// #cgo LDFLAGS: -L../../dist
+import "C"
+
+func serializeFloat32(vector []float32) ([]byte, error) {
+	buf := new(bytes.Buffer)
+	err := binary.Write(buf, binary.LittleEndian, vector)
+	if err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+func main() {
+	sqlite_vec.Auto()
+	db, err := sql.Open("sqlite3", ":memory:")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer db.Close()
+
+	var sqliteVersion string
+	var vecVersion string
+	err = db.QueryRow("select sqlite_version(), vec_version()").Scan(&sqliteVersion, &vecVersion)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("sqlite_version=%s, vec_version=%s\n", sqliteVersion, vecVersion)
+
+	_, err = db.Exec("CREATE VIRTUAL TABLE vec_items USING vec0(embedding float[8])")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	items := map[int][]float32{
+		1: {0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8},
+		2: {0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8},
+	}
+
+	for id, values := range items {
+		v, err := serializeFloat32(values)
+		if err != nil {
+			log.Fatal(err)
+		}
+		_, err = db.Exec("INSERT INTO vec_items(rowid, embedding) VALUES (?, ?)", id, v)
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+
+	q := []float32{0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8}
+	query, err := serializeFloat32(q)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	rows, err := db.Query(`
+		SELECT
+			rowid,
+			distance
+		FROM vec_items
+		WHERE embedding MATCH ?
+		ORDER BY distance
+		LIMIT 5
+	`, query)
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	for rows.Next() {
+		var rowid int64
+		var distance float64
+		err = rows.Scan(&rowid, &distance)
+		if err != nil {
+			log.Fatal(err)
+		}
+		fmt.Printf("rowid=%d, distance=%f\n", rowid, distance)
+	}
+	err = rows.Err()
+	if err != nil {
+		log.Fatal((err))
+	}
+
+}