From 59586dcd313bd067c2b94c118a9d20663ab3c8d0 Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Sat, 29 Aug 2020 23:02:19 +0800
Subject: [PATCH] Fix unnecessary duplicated primary condition when using Save,
 close #3330

---
 finisher_api.go      |  9 ++-------
 tests/update_test.go | 24 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/finisher_api.go b/finisher_api.go
index 2cde3c31..824f2a2e 100644
--- a/finisher_api.go
+++ b/finisher_api.go
@@ -32,17 +32,12 @@ func (db *DB) Save(value interface{}) (tx *DB) {
 		tx.callbacks.Create().Execute(tx)
 	case reflect.Struct:
 		if err := tx.Statement.Parse(value); err == nil && tx.Statement.Schema != nil {
-			where := clause.Where{Exprs: make([]clause.Expression, len(tx.Statement.Schema.PrimaryFields))}
-			for idx, pf := range tx.Statement.Schema.PrimaryFields {
-				if pv, isZero := pf.ValueOf(reflectValue); isZero {
+			for _, pf := range tx.Statement.Schema.PrimaryFields {
+				if _, isZero := pf.ValueOf(reflectValue); isZero {
 					tx.callbacks.Create().Execute(tx)
 					return
-				} else {
-					where.Exprs[idx] = clause.Eq{Column: pf.DBName, Value: pv}
 				}
 			}
-
-			tx.Statement.AddClause(where)
 		}
 
 		fallthrough
diff --git a/tests/update_test.go b/tests/update_test.go
index e52dc652..d566c04d 100644
--- a/tests/update_test.go
+++ b/tests/update_test.go
@@ -2,6 +2,7 @@ package tests_test
 
 import (
 	"errors"
+	"regexp"
 	"sort"
 	"strings"
 	"testing"
@@ -586,3 +587,26 @@ func TestUpdateFromSubQuery(t *testing.T) {
 		t.Errorf("name should be %v, but got %v", user.Company.Name, result.Name)
 	}
 }
+
+func TestSave(t *testing.T) {
+	user := *GetUser("save", Config{})
+	DB.Create(&user)
+
+	if err := DB.First(&User{}, "name = ?", "save").Error; err != nil {
+		t.Fatalf("failed to find created user")
+	}
+
+	user.Name = "save2"
+	DB.Save(&user)
+
+	var result User
+	if err := DB.First(&result, "name = ?", "save2").Error; err != nil || result.ID != user.ID {
+		t.Fatalf("failed to find updated user")
+	}
+
+	dryDB := DB.Session(&gorm.Session{DryRun: true})
+	stmt := dryDB.Save(&user).Statement
+	if !regexp.MustCompile("WHERE .id. = [^ ]+$").MatchString(stmt.SQL.String()) {
+		t.Fatalf("invalid updating SQL, got %v", stmt.SQL.String())
+	}
+}