diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
index d4fbfc1..0cda728 100644
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -20,6 +20,7 @@ jobs:
       uses: actions/setup-go@v3
       with:
         go-version: stable
+        cache: true
 
     - name: Build
       run: go build -v ./...
diff --git a/const.go b/const.go
index f437bdb..0904b87 100644
--- a/const.go
+++ b/const.go
@@ -1,5 +1,7 @@
 package sqlite3
 
+import "strconv"
+
 const (
 	_OK   = 0   /* Successful result */
 	_ROW  = 100 /* sqlite3_step() has another row ready */
@@ -175,3 +177,20 @@ const (
 	BLOB    Datatype = 4
 	NULL    Datatype = 5
 )
+
+func (t Datatype) String() string {
+	const name = "INTEGERFLOATTEXTBLOBNULL"
+	switch t {
+	case INTEGER:
+		return name[0:7]
+	case FLOAT:
+		return name[7:12]
+	case TEXT:
+		return name[12:16]
+	case BLOB:
+		return name[16:20]
+	case NULL:
+		return name[20:24]
+	}
+	return strconv.FormatUint(uint64(t), 10)
+}
diff --git a/const_test.go b/const_test.go
new file mode 100644
index 0000000..5cf97bf
--- /dev/null
+++ b/const_test.go
@@ -0,0 +1,24 @@
+package sqlite3
+
+import "testing"
+
+func TestDatatype_String(t *testing.T) {
+	tests := []struct {
+		data Datatype
+		want string
+	}{
+		{INTEGER, "INTEGER"},
+		{FLOAT, "FLOAT"},
+		{TEXT, "TEXT"},
+		{BLOB, "BLOB"},
+		{NULL, "NULL"},
+		{10, "10"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.want, func(t *testing.T) {
+			if got := tt.data.String(); got != tt.want {
+				t.Errorf("got %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
diff --git a/go.mod b/go.mod
index 4744b87..cf63a4c 100644
--- a/go.mod
+++ b/go.mod
@@ -5,6 +5,5 @@ go 1.19
 require (
 	github.com/ncruces/julianday v0.1.4
 	github.com/tetratelabs/wazero v1.0.0-pre.8
+	golang.org/x/sync v0.1.0
 )
-
-require golang.org/x/sync v0.1.0
diff --git a/stmt.go b/stmt.go
index 4c9aff1..a7e4daf 100644
--- a/stmt.go
+++ b/stmt.go
@@ -49,6 +49,16 @@ func (s *Stmt) Err() error {
 	return s.err
 }
 
+func (s *Stmt) Exec() error {
+	for s.Step() {
+	}
+	err := s.Err()
+	if rerr := s.Reset(); err == nil {
+		err = rerr
+	}
+	return err
+}
+
 func (s *Stmt) BindBool(param int, value bool) error {
 	if value {
 		return s.BindInt64(param, 1)
@@ -111,6 +121,15 @@ func (s *Stmt) BindNull(param int) error {
 	return s.c.error(r[0])
 }
 
+func (s *Stmt) ColumnType(col int) Datatype {
+	r, err := s.c.api.columnType.Call(s.c.ctx,
+		uint64(s.handle), uint64(col))
+	if err != nil {
+		panic(err)
+	}
+	return Datatype(r[0])
+}
+
 func (s *Stmt) ColumnBool(col int) bool {
 	if i := s.ColumnInt64(col); i != 0 {
 		return true
@@ -132,7 +151,7 @@ func (s *Stmt) ColumnInt64(col int) int64 {
 }
 
 func (s *Stmt) ColumnFloat(col int) float64 {
-	r, err := s.c.api.columnInteger.Call(s.c.ctx,
+	r, err := s.c.api.columnFloat.Call(s.c.ctx,
 		uint64(s.handle), uint64(col))
 	if err != nil {
 		panic(err)
@@ -181,7 +200,7 @@ func (s *Stmt) ColumnBlob(col int, buf []byte) []byte {
 			panic(err)
 		}
 		s.err = s.c.error(r[0])
-		return nil
+		return buf[0:0]
 	}
 
 	r, err = s.c.api.columnBytes.Call(s.c.ctx,
diff --git a/stmt_test.go b/stmt_test.go
new file mode 100644
index 0000000..cf6dc2c
--- /dev/null
+++ b/stmt_test.go
@@ -0,0 +1,325 @@
+package sqlite3
+
+import (
+	"math"
+	"testing"
+)
+
+func TestStmt(t *testing.T) {
+	db, err := Open(":memory:")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	err = db.Exec(`CREATE TABLE IF NOT EXISTS test (col)`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	stmt, _, err := db.Prepare(`INSERT INTO test(col) VALUES(?)`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer stmt.Close()
+
+	err = stmt.BindBool(1, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindBool(1, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindInt(1, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindFloat(1, math.Pi)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindNull(1)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindText(1, "")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindText(1, "text")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindBlob(1, []byte("blob"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.BindBlob(1, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Exec()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// The table should have: 0, 1, 2, π, NULL, "", "text", `blob`, NULL
+	stmt, _, err = db.Prepare(`SELECT col FROM test`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != INTEGER {
+			t.Errorf("got %v, want INTEGER", got)
+		}
+		if got := stmt.ColumnBool(0); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+		if got := stmt.ColumnInt(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnText(0); got != "0" {
+			t.Errorf("got %q, want zero", got)
+		}
+		if got := stmt.ColumnBlob(0, nil); string(got) != "0" {
+			t.Errorf("got %q, want zero", got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != INTEGER {
+			t.Errorf("got %v, want INTEGER", got)
+		}
+		if got := stmt.ColumnBool(0); got != true {
+			t.Errorf("got %v, want true", got)
+		}
+		if got := stmt.ColumnInt(0); got != 1 {
+			t.Errorf("got %v, want one", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 1 {
+			t.Errorf("got %v, want one", got)
+		}
+		if got := stmt.ColumnText(0); got != "1" {
+			t.Errorf("got %q, want one", got)
+		}
+		if got := stmt.ColumnBlob(0, nil); string(got) != "1" {
+			t.Errorf("got %q, want one", got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != INTEGER {
+			t.Errorf("got %v, want INTEGER", got)
+		}
+		if got := stmt.ColumnBool(0); got != true {
+			t.Errorf("got %v, want true", got)
+		}
+		if got := stmt.ColumnInt(0); got != 2 {
+			t.Errorf("got %v, want two", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 2 {
+			t.Errorf("got %v, want two", got)
+		}
+		if got := stmt.ColumnText(0); got != "2" {
+			t.Errorf("got %q, want two", got)
+		}
+		if got := stmt.ColumnBlob(0, nil); string(got) != "2" {
+			t.Errorf("got %q, want two", got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != FLOAT {
+			t.Errorf("got %v, want FLOAT", got)
+		}
+		if got := stmt.ColumnBool(0); got != true {
+			t.Errorf("got %v, want true", got)
+		}
+		if got := stmt.ColumnInt(0); got != 3 {
+			t.Errorf("got %v, want three", got)
+		}
+		if got := stmt.ColumnFloat(0); got != math.Pi {
+			t.Errorf("got %v, want π", got)
+		}
+		if got := stmt.ColumnText(0); got != "3.14159265358979" {
+			t.Errorf("got %q, want π", got)
+		}
+		if got := stmt.ColumnBlob(0, nil); string(got) != "3.14159265358979" {
+			t.Errorf("got %q, want π", got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != NULL {
+			t.Errorf("got %v, want NULL", got)
+		}
+		if got := stmt.ColumnBool(0); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+		if got := stmt.ColumnInt(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnText(0); got != "" {
+			t.Errorf("got %q, want empty", got)
+		}
+		if got := stmt.ColumnBlob(0, nil); got != nil {
+			t.Errorf("got %q, want nil", got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != TEXT {
+			t.Errorf("got %v, want TEXT", got)
+		}
+		if got := stmt.ColumnBool(0); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+		if got := stmt.ColumnInt(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnText(0); got != "" {
+			t.Errorf("got %q, want empty", got)
+		}
+		if got := stmt.ColumnBlob(0, nil); got != nil {
+			t.Errorf("got %q, want nil", got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != TEXT {
+			t.Errorf("got %v, want TEXT", got)
+		}
+		if got := stmt.ColumnBool(0); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+		if got := stmt.ColumnInt(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnText(0); got != "text" {
+			t.Errorf(`got %q, want "text"`, got)
+		}
+		if got := stmt.ColumnBlob(0, nil); string(got) != "text" {
+			t.Errorf(`got %q, want "text"`, got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != BLOB {
+			t.Errorf("got %v, want BLOB", got)
+		}
+		if got := stmt.ColumnBool(0); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+		if got := stmt.ColumnInt(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnText(0); got != "blob" {
+			t.Errorf(`got %q, want "blob"`, got)
+		}
+		if got := stmt.ColumnBlob(0, nil); string(got) != "blob" {
+			t.Errorf(`got %q, want "blob"`, got)
+		}
+	}
+
+	if stmt.Step() {
+		if got := stmt.ColumnType(0); got != NULL {
+			t.Errorf("got %v, want NULL", got)
+		}
+		if got := stmt.ColumnBool(0); got != false {
+			t.Errorf("got %v, want false", got)
+		}
+		if got := stmt.ColumnInt(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnFloat(0); got != 0 {
+			t.Errorf("got %v, want zero", got)
+		}
+		if got := stmt.ColumnText(0); got != "" {
+			t.Errorf("got %q, want empty", got)
+		}
+		if got := stmt.ColumnBlob(0, nil); got != nil {
+			t.Errorf("got %q, want nil", got)
+		}
+	}
+
+	err = stmt.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = db.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+}
diff --git a/tests/dir_test.go b/tests/dir_test.go
index dd9b71d..10ba8d3 100644
--- a/tests/dir_test.go
+++ b/tests/dir_test.go
@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/ncruces/go-sqlite3"
+	_ "github.com/ncruces/go-sqlite3/embed"
 )
 
 func TestDir(t *testing.T) {
diff --git a/tests/parallel_test.go b/tests/parallel_test.go
index e3c36f6..df6f077 100644
--- a/tests/parallel_test.go
+++ b/tests/parallel_test.go
@@ -5,7 +5,6 @@ import (
 	"path/filepath"
 	"runtime"
 	"testing"
-	"time"
 
 	"golang.org/x/sync/errgroup"
 
@@ -41,12 +40,12 @@ func TestParallel(t *testing.T) {
 
 		err = db.Exec(`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
 		if err != nil {
-			t.Fatal(err)
+			return err
 		}
 
 		err = db.Exec(`INSERT INTO users(id, name) VALUES(0, 'go'), (1, 'zig'), (2, 'whatever')`)
 		if err != nil {
-			t.Fatal(err)
+			return err
 		}
 
 		return db.Close()
@@ -104,7 +103,6 @@ func TestParallel(t *testing.T) {
 		} else {
 			group.Go(writer)
 		}
-		time.Sleep(time.Microsecond)
 	}
 	err = group.Wait()
 	if err != nil {