diff --git a/clause/clause.go b/clause/clause.go
index 9a5d1273..b3e96332 100644
--- a/clause/clause.go
+++ b/clause/clause.go
@@ -24,42 +24,46 @@ type Builder interface {
 
 // Clause
 type Clause struct {
-	Name                 string // WHERE
-	Priority             float64
-	BeforeExpressions    []Expression
-	AfterNameExpressions []Expression
-	AfterExpressions     []Expression
-	Expression           Expression
-	Builder              ClauseBuilder
+	Name                string // WHERE
+	BeforeExpression    Expression
+	AfterNameExpression Expression
+	AfterExpression     Expression
+	Expression          Expression
+	Builder             ClauseBuilder
 }
 
 // Build build clause
 func (c Clause) Build(builder Builder) {
 	if c.Builder != nil {
 		c.Builder(c, builder)
-	} else {
-		builders := c.BeforeExpressions
+	} else if c.Expression != nil {
+		if c.BeforeExpression != nil {
+			c.BeforeExpression.Build(builder)
+			builder.WriteByte(' ')
+		}
+
 		if c.Name != "" {
-			builders = append(builders, Expr{SQL: c.Name})
+			builder.WriteString(c.Name)
+			builder.WriteByte(' ')
 		}
 
-		builders = append(builders, c.AfterNameExpressions...)
-		if c.Expression != nil {
-			builders = append(builders, c.Expression)
+		if c.AfterNameExpression != nil {
+			c.BeforeExpression.Build(builder)
+			builder.WriteByte(' ')
 		}
 
-		for idx, expr := range append(builders, c.AfterExpressions...) {
-			if idx != 0 {
-				builder.WriteByte(' ')
-			}
-			expr.Build(builder)
+		c.Expression.Build(builder)
+
+		if c.AfterExpression != nil {
+			builder.WriteByte(' ')
+			c.AfterExpression.Build(builder)
 		}
 	}
 }
 
 const (
-	PrimaryKey   string = "@@@priamry_key@@@"
-	CurrentTable string = "@@@table@@@"
+	PrimaryKey   string = "@@@py@@@" // primary key
+	CurrentTable string = "@@@ct@@@" // current table
 )
 
 var (
diff --git a/clause/locking_test.go b/clause/locking_test.go
index 5ca30ef0..0e607312 100644
--- a/clause/locking_test.go
+++ b/clause/locking_test.go
@@ -7,7 +7,7 @@ import (
 	"gorm.io/gorm/clause"
 )
 
-func TestFor(t *testing.T) {
+func TestLocking(t *testing.T) {
 	results := []struct {
 		Clauses []clause.Interface
 		Result  string
diff --git a/clause/where.go b/clause/where.go
index 08c78b22..015addf8 100644
--- a/clause/where.go
+++ b/clause/where.go
@@ -14,7 +14,7 @@ func (where Where) Name() string {
 func (where Where) Build(builder Builder) {
 	// Switch position if the first query expression is a single Or condition
 	for idx, expr := range where.Exprs {
-		if v, ok := expr.(OrConditions); (!ok && expr != nil) || len(v.Exprs) > 1 {
+		if v, ok := expr.(OrConditions); !ok || len(v.Exprs) > 1 {
 			if idx != 0 {
 				where.Exprs[0], where.Exprs[idx] = where.Exprs[idx], where.Exprs[0]
 			}
@@ -23,17 +23,15 @@ func (where Where) Build(builder Builder) {
 	}
 
 	for idx, expr := range where.Exprs {
-		if expr != nil {
-			if idx > 0 {
-				if v, ok := expr.(OrConditions); ok && len(v.Exprs) == 1 {
-					builder.WriteString(" OR ")
-				} else {
-					builder.WriteString(" AND ")
-				}
+		if idx > 0 {
+			if v, ok := expr.(OrConditions); ok && len(v.Exprs) == 1 {
+				builder.WriteString(" OR ")
+			} else {
+				builder.WriteString(" AND ")
 			}
-
-			expr.Build(builder)
 		}
+
+		expr.Build(builder)
 	}
 
 	return
diff --git a/clause/where_test.go b/clause/where_test.go
index 894e11f4..95bba820 100644
--- a/clause/where_test.go
+++ b/clause/where_test.go
@@ -27,7 +27,7 @@ func TestWhere(t *testing.T) {
 		},
 		{
 			[]clause.Interface{clause.Select{}, clause.From{}, clause.Where{
-				Exprs: []clause.Expression{clause.Or(), clause.Or(clause.Neq{Column: "name", Value: "jinzhu"}), clause.Eq{Column: clause.PrimaryColumn, Value: "1"}, clause.Gt{Column: "age", Value: 18}},
+				Exprs: []clause.Expression{clause.Or(clause.Neq{Column: "name", Value: "jinzhu"}), clause.Eq{Column: clause.PrimaryColumn, Value: "1"}, clause.Gt{Column: "age", Value: 18}},
 			}},
 			"SELECT * FROM `users` WHERE `users`.`id` = ? OR `name` <> ? AND `age` > ?", []interface{}{"1", "jinzhu", 18},
 		},
diff --git a/finisher_api.go b/finisher_api.go
index e94fd095..434f0e22 100644
--- a/finisher_api.go
+++ b/finisher_api.go
@@ -32,13 +32,14 @@ func (db *DB) Save(value interface{}) (tx *DB) {
 			for idx, pf := range tx.Statement.Schema.PrimaryFields {
 				if pv, isZero := pf.ValueOf(reflectValue); isZero {
 					tx.callbacks.Create().Execute(tx)
-					where.Exprs[idx] = clause.Eq{Column: pf.DBName, Value: pv}
 					return
+				} else {
+					where.Exprs[idx] = clause.Eq{Column: pf.DBName, Value: pv}
 				}
 			}
-		}
 
-		tx.Statement.AddClause(where)
+			tx.Statement.AddClause(where)
+		}
 	}
 
 	if len(tx.Statement.Selects) == 0 {
diff --git a/statement.go b/statement.go
index 2c814547..ec9e021f 100644
--- a/statement.go
+++ b/statement.go
@@ -201,19 +201,19 @@ func (stmt *Statement) AddVar(writer clause.Writer, vars ...interface{}) {
 func (stmt *Statement) AddClause(v clause.Interface) {
 	if optimizer, ok := v.(StatementModifier); ok {
 		optimizer.ModifyStatement(stmt)
+	} else {
+		c, ok := stmt.Clauses[v.Name()]
+		if !ok {
+			c.Name = v.Name()
+		}
+		v.MergeClause(&c)
+		stmt.Clauses[v.Name()] = c
 	}
-
-	c, ok := stmt.Clauses[v.Name()]
-	if !ok {
-		c.Name = v.Name()
-	}
-	v.MergeClause(&c)
-	stmt.Clauses[v.Name()] = c
 }
 
 // AddClauseIfNotExists add clause if not exists
 func (stmt *Statement) AddClauseIfNotExists(v clause.Interface) {
-	if c, ok := stmt.Clauses[v.Name()]; !ok && c.Expression == nil {
+	if c, ok := stmt.Clauses[v.Name()]; !ok || c.Expression == nil {
 		stmt.AddClause(v)
 	}
 }