diff --git a/tpl/macros_struct.twig b/tpl/macros_struct.twig
index e2c50e4..c8f1847 100644
--- a/tpl/macros_struct.twig
+++ b/tpl/macros_struct.twig
@@ -73,6 +73,7 @@ type {{ json_fields_type }} struct{
 {% set delete_by = select_by %}
 {% set delete_where_expr = select_where_expr %}
 {% set pkey_column_expr = pkey|map(f => "`#{f.name}`")|join(',') %}
+{% set pkey_update_expr = pkey|map(f => "`#{f.name}`=VALUES(`#{f.name}`)")|join(',') %}
 {% set pkey_values_expr = arr_fill('?', pkey|length)|join(',') %}
 
 {{ _self.changed_fields_methods(s.name, nopkey) }}
@@ -140,10 +141,10 @@ func Save{{ ctx.s.name }}Diff(ctx context.Context, dbe metadb.Execer, rec {{ ctx
 	valuesBuilder.WriteString(" VALUES ({{ ctx.pkey_values_expr }}")
 
 	var updateBuilder strings.Builder
-	updateBuilder.Grow({{ 25 + ctx.insert_update_expr|length }})
-	updateBuilder.WriteString(" ON DUPLICATE KEY UPDATE ")
+	updateBuilder.Grow({{ 25 + ctx.pkey_update_expr|length + ctx.insert_update_expr|length }})
+	updateBuilder.WriteString(" ON DUPLICATE KEY UPDATE {{ ctx.pkey_update_expr }}")
 
-	values := make([]any, 0, 10)
+	values := make([]any, 0, {{ ctx.insert_fields|length }})
 	{% for f in ctx.pkey %}
 	values = append(values, rec.{{ f|fname }})
 	{% endfor %}
@@ -166,7 +167,7 @@ func Save{{ ctx.s.name }}Diff(ctx context.Context, dbe metadb.Execer, rec {{ ctx
 
 	{% if has_token(ctx.s, 'table_json_kv') %}
 	var jsonBuilder strings.Builder
-	jsonBuilder.Grow(255)
+	jsonBuilder.Grow(255) // TODO: is it possible calc grow length?
 
 	jsonValues := make([]any, 0, {{ ctx.json_fields|length }})
 	{% for f in ctx.json_fields %}