From f6117b7f3dd21629b8196c376b0284d71672d1c7 Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Wed, 9 Sep 2020 16:26:11 +0800
Subject: [PATCH] Should not diplay SubQuery SQL log, close #3437

---
 logger/logger.go | 14 +++++++++-----
 statement.go     |  3 ++-
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/logger/logger.go b/logger/logger.go
index 0b0a7377..831192fc 100644
--- a/logger/logger.go
+++ b/logger/logger.go
@@ -2,6 +2,7 @@ package logger
 
 import (
 	"context"
+	"io/ioutil"
 	"log"
 	"os"
 	"time"
@@ -54,11 +55,14 @@ type Interface interface {
 	Trace(ctx context.Context, begin time.Time, fc func() (string, int64), err error)
 }
 
-var Default = New(log.New(os.Stdout, "\r\n", log.LstdFlags), Config{
-	SlowThreshold: 100 * time.Millisecond,
-	LogLevel:      Warn,
-	Colorful:      true,
-})
+var (
+	Discard = New(log.New(ioutil.Discard, "", log.LstdFlags), Config{})
+	Default = New(log.New(os.Stdout, "\r\n", log.LstdFlags), Config{
+		SlowThreshold: 100 * time.Millisecond,
+		LogLevel:      Warn,
+		Colorful:      true,
+	})
+)
 
 func New(writer Writer, config Config) Interface {
 	var (
diff --git a/statement.go b/statement.go
index e16cf0ff..ee80f8cd 100644
--- a/statement.go
+++ b/statement.go
@@ -12,6 +12,7 @@ import (
 	"sync"
 
 	"gorm.io/gorm/clause"
+	"gorm.io/gorm/logger"
 	"gorm.io/gorm/schema"
 	"gorm.io/gorm/utils"
 )
@@ -189,7 +190,7 @@ func (stmt *Statement) AddVar(writer clause.Writer, vars ...interface{}) {
 				writer.WriteString("(NULL)")
 			}
 		case *DB:
-			subdb := v.Session(&Session{DryRun: true, WithConditions: true}).getInstance()
+			subdb := v.Session(&Session{Logger: logger.Discard, DryRun: true, WithConditions: true}).getInstance()
 			subdb.Statement.Vars = append(subdb.Statement.Vars, stmt.Vars...)
 			subdb.callbacks.Query().Execute(subdb)
 			writer.WriteString(subdb.Statement.SQL.String())