diff --git a/callbacks/scan.go b/callbacks/scan.go
index c9f948b1..f8f1ef54 100644
--- a/callbacks/scan.go
+++ b/callbacks/scan.go
@@ -5,6 +5,7 @@ import (
 	"reflect"
 
 	"github.com/jinzhu/gorm"
+	"github.com/jinzhu/gorm/schema"
 )
 
 func Scan(rows *sql.Rows, db *gorm.DB) {
@@ -52,14 +53,17 @@ func Scan(rows *sql.Rows, db *gorm.DB) {
 		case reflect.Slice, reflect.Array:
 			isPtr := db.Statement.ReflectValue.Type().Elem().Kind() == reflect.Ptr
 			db.Statement.ReflectValue.Set(reflect.MakeSlice(db.Statement.ReflectValue.Type(), 0, 0))
+			fields := make([]*schema.Field, len(columns))
+
+			for idx, column := range columns {
+				fields[idx] = db.Statement.Schema.LookUpField(column)
+			}
 
 			for rows.Next() {
 				elem := reflect.New(db.Statement.Schema.ModelType).Elem()
-				for idx, column := range columns {
-					if field := db.Statement.Schema.LookUpField(column); field != nil {
+				for idx, field := range fields {
+					if field != nil {
 						values[idx] = field.ReflectValueOf(elem).Addr().Interface()
-					} else if db.RowsAffected == 0 {
-						values[idx] = sql.RawBytes{}
 					}
 				}
 
diff --git a/logger/logger.go b/logger/logger.go
index d3b97b9d..2a765628 100644
--- a/logger/logger.go
+++ b/logger/logger.go
@@ -121,7 +121,7 @@ func (l logger) Error(msg string, data ...interface{}) {
 
 // Trace print sql message
 func (l logger) Trace(begin time.Time, fc func() (string, int64), err error) {
-	if elapsed := time.Now().Sub(begin); err != nil || elapsed > l.SlowThreshold {
+	if elapsed := time.Now().Sub(begin); err != nil || (elapsed > l.SlowThreshold && l.SlowThreshold != 0) {
 		sql, rows := fc()
 		fileline := utils.FileWithLineNum()
 		if err != nil {
diff --git a/tests/docker-compose.yml b/tests/docker-compose.yml
index 79bf5fc3..6bf3fadf 100644
--- a/tests/docker-compose.yml
+++ b/tests/docker-compose.yml
@@ -15,8 +15,8 @@ services:
     ports:
       - 9920:5432
     environment:
-      - POSTGRES_USER=gorm
       - POSTGRES_DB=gorm
+      - POSTGRES_USER=gorm
       - POSTGRES_PASSWORD=gorm
   mssql:
     image: 'mcmoe/mssqldocker:latest'