diff --git a/x/sqlbuilder/upserter/execer.go b/x/sqlbuilder/upserter/execer.go
index 2d7ca30..1710d41 100644
--- a/x/sqlbuilder/upserter/execer.go
+++ b/x/sqlbuilder/upserter/execer.go
@@ -1,12 +1,9 @@
 package upserter
 
 import (
-	"bytes"
 	"context"
 	"database/sql/driver"
 	"fmt"
-	"reflect"
-	"time"
 
 	"github.com/upfluence/errors"
 	"github.com/upfluence/sql"
@@ -127,6 +124,12 @@ func newExecer(te txExecutor, stmt Statement) sqlbuilder.Execer {
 		}
 	}
 
+	var selectClauses = []sqlbuilder.Marker{oneMarker}
+
+	for _, m := range stmt.SetValues {
+		selectClauses = append(selectClauses, &assertMarker{Marker: m})
+	}
+
 	var (
 		clauses = make([]sqlbuilder.PredicateClause, len(stmt.QueryValues))
 
@@ -136,7 +139,7 @@ func newExecer(te txExecutor, stmt Statement) sqlbuilder.Execer {
 			sfs: make([]string, len(stmt.SetValues)),
 			ss: sqlbuilder.SelectStatement{
 				Table:         stmt.Table,
-				SelectClauses: append([]sqlbuilder.Marker{oneMarker}, stmt.SetValues...),
+				SelectClauses: selectClauses,
 			},
 			us: sqlbuilder.UpdateStatement{
 				Table:  stmt.Table,
@@ -199,49 +202,19 @@ func newExecer(te txExecutor, stmt Statement) sqlbuilder.Execer {
 	return &e
 }
 
-func cloneValue(v any) (any, error) {
-	if dv, ok := v.(driver.Valuer); ok {
-		vv, err := dv.Value()
-
-		if err != nil {
-			return nil, err
-		}
-
-		if vv != nil {
-			v = vv
-		}
-	}
-
-	return reflect.New(reflect.TypeOf(v)).Interface(), nil
+type assertMarker struct {
+	sqlbuilder.Marker
 }
 
-func equalValues(x, y any) (bool, error) {
-	if dy, ok := y.(driver.Valuer); ok {
-		yy, err := dy.Value()
-
-		if err != nil {
-			return false, err
-		}
-
-		if yy != nil {
-			y = yy
-		}
-	}
-
-	switch yy := y.(type) {
-	case time.Time:
-		if xx, ok := x.(time.Time); ok {
-			return xx.Equal(yy), nil
-		}
-	case []byte:
-		if xx, ok := x.([]byte); ok {
-			return bytes.Equal(yy, xx), nil
-		}
-	default:
-		return reflect.DeepEqual(x, y), nil
-	}
+func (am *assertMarker) WriteTo(qw sqlbuilder.QueryWriter, vs map[string]interface{}) error {
+	_, err := fmt.Fprintf(
+		qw,
+		"%s = %s",
+		am.ToSQL(),
+		qw.RedeemVariable(vs["assert_"+am.Binding()]),
+	)
 
-	return false, nil
+	return err
 }
 
 func (e *execer) Exec(ctx context.Context, vs map[string]interface{}) (sql.Result, error) {
@@ -271,13 +244,11 @@ func (e *execer) Exec(ctx context.Context, vs map[string]interface{}) (sql.Resul
 			return nil, sqlbuilder.ErrMissingKey{Key: f}
 		}
 
-		var err error
+		var val sql.NullBool
 
-		existing[f], err = cloneValue(v)
+		qvs["assert_"+f] = v
 
-		if err != nil {
-			return nil, err
-		}
+		existing[f] = &val
 	}
 
 	if m := e.returningMarker; m != nil {
@@ -296,14 +267,9 @@ func (e *execer) Exec(ctx context.Context, vs map[string]interface{}) (sql.Resul
 			pristine := true
 
 			for _, sf := range e.sfs {
-				ok, err := equalValues(reflect.ValueOf(existing[sf]).Elem().Interface(), vs[sf])
-
-				if err != nil {
-					return err
-				}
-
-				if !ok {
+				if val := existing[sf].(*sql.NullBool); !val.Bool {
 					pristine = false
+
 					break
 				}
 			}