Introduce ScanValues.

bench_test.go

@@ -5,20 +5,42 @@ import (
 	"testing"
 )
 
-func BenchmarkScan(b *testing.B) {
-	b.StopTimer()
-	db, _ := Open("")
-	defer db.Close()
+func fill(db *Conn, n int) {
 	db.Exec("DROP TABLE IF EXISTS test")
 	db.Exec("CREATE TABLE test (id INTEGER PRIMARY KEY AUTOINCREMENT, float_num REAL, int_num INTEGER, a_string TEXT)")
-	db.Begin()
 	s, _ := db.Prepare("INSERT INTO test (float_num, int_num, a_string) VALUES (?, ?, ?)")
 
-	for i := 0; i < 1000; i++ {
+	db.Begin()
+	for i := 0; i < n; i++ {
 		s.Exec(float64(i)*float64(3.14), i, "hello")
 	}
 	s.Finalize()
 	db.Commit()
+}
+
+func BenchmarkValuesScan(b *testing.B) {
+	b.StopTimer()
+	db, _ := Open("")
+	defer db.Close()
+	fill(db, 1000)
+
+	b.StartTimer()
+	for i := 0; i < b.N; i++ {
+		cs, _ := db.Prepare("SELECT float_num, int_num, a_string FROM test")
+
+		values := make([]interface{}, 3)
+		for Must(cs.Next()) {
+			cs.ScanValues(values)
+		}
+		cs.Finalize()
+	}
+}
+
+func BenchmarkScan(b *testing.B) {
+	b.StopTimer()
+	db, _ := Open("")
+	defer db.Close()
+	fill(db, 1000)
 
 	b.StartTimer()
 	for i := 0; i < b.N; i++ {
@@ -39,16 +61,7 @@ func BenchmarkNamedScan(b *testing.B) {
 	b.StopTimer()
 	db, _ := Open("")
 	defer db.Close()
-	db.Exec("DROP TABLE IF EXISTS test")
-	db.Exec("CREATE TABLE test (id INTEGER PRIMARY KEY AUTOINCREMENT, float_num REAL, int_num INTEGER, a_string TEXT)")
-	db.Begin()
-	s, _ := db.Prepare("INSERT INTO test (float_num, int_num, a_string) VALUES (?, ?, ?)")
-
-	for i := 0; i < 1000; i++ {
-		s.Exec(float64(i)*float64(3.14), i, "hello")
-	}
-	s.Finalize()
-	db.Commit()
+	fill(db, 1000)
 
 	b.StartTimer()
 	for i := 0; i < b.N; i++ {
@@ -66,18 +79,25 @@ func BenchmarkNamedScan(b *testing.B) {
 }
 
 func BenchmarkInsert(b *testing.B) {
+	db, _ := Open("")
+	defer db.Close()
+	fill(db, b.N)
+}
+
+func BenchmarkNamedInsert(b *testing.B) {
 	db, _ := Open("")
 	defer db.Close()
 	db.Exec("DROP TABLE IF EXISTS test")
 	db.Exec("CREATE TABLE test (id INTEGER PRIMARY KEY AUTOINCREMENT," +
 		" float_num REAL, int_num INTEGER, a_string TEXT)")
 	s, _ := db.Prepare("INSERT INTO test (float_num, int_num, a_string)" +
-		" VALUES (?, ?, ?)")
+		" VALUES (:f, :i, :s)")
 	defer s.Finalize()
 
 	db.Begin()
 	for i := 0; i < b.N; i++ {
-		s.Exec(float64(i)*float64(3.14), i, "hello")
+		s.NamedBind("f", float64(i)*float64(3.14), "i", i, "s", "hello")
+		s.Next()
 	}
 	db.Commit()
 }

driver.go

@@ -121,8 +121,6 @@ func (s *stmtImpl) Next(dest []interface{}) error {
 	if !ok {
 		return io.EOF
 	}
-	for i := range dest {
-		dest[i] = s.s.ScanValue(i)
-	}
+	s.s.ScanValues(dest)
 	return nil
 }

sqlite.go

@@ -477,7 +477,7 @@ func (s *Stmt) BindParameterCount() int {
 	return int(C.sqlite3_bind_parameter_count(s.stmt))
 }
 
-// Index of a parameter with a given name
+// Index of a parameter with a given name (cached)
 // Calls http://sqlite.org/c3ref/bind_parameter_index.html
 func (s *Stmt) BindParameterIndex(name string) (int, error) {
 	if s.params == nil {
@@ -511,7 +511,7 @@ func (s *Stmt) BindParameterName(i int) (string, error) {
 
 // Bind parameters by their name (name1, value1, ...)
 func (s *Stmt) NamedBind(args ...interface{}) error {
-	err := s.Reset() // TODO sqlite3_clear_bindings?
+	err := s.Reset()
 	if err != nil {
 		return err
 	}
@@ -539,7 +539,7 @@ func (s *Stmt) NamedBind(args ...interface{}) error {
 // Calls sqlite3_bind_parameter_count and sqlite3_bind_(blob|double|int|int64|null|text) depending on args type.
 // http://sqlite.org/c3ref/bind_blob.html
 func (s *Stmt) Bind(args ...interface{}) error {
-	err := s.Reset() // TODO sqlite3_clear_bindings?
+	err := s.Reset()
 	if err != nil {
 		return err
 	}
@@ -890,6 +890,13 @@ func (s *Stmt) ScanValue(index int) (value interface{}) {
 	return
 }
 
+// Like ScanValue on several columns
+func (s *Stmt) ScanValues(values []interface{}) {
+	for i := 0; i < len(values); i++ {
+		values[i] = s.ScanValue(i)
+	}
+}
+
 // The leftmost column/index is number 0.
 // Returns true when column is null.
 // Calls sqlite3_column_text.