diff --git a/application.go b/application.go
index bad8ab4..9f7d525 100644
--- a/application.go
+++ b/application.go
@@ -1,7 +1,6 @@
 package hotime
 
 import (
-	"./tools/db"
 	"bytes"
 	"database/sql"
 	"encoding/json"
@@ -23,7 +22,7 @@ type Application struct {
 	Port            string                     //端口号
 	TLSPort         string                     //ssl访问端口号
 	connectListener []func(this *Context) bool //所有的访问监听,true按原计划继续使用，false表示有监听器处理
-	connectDbFunc   func(err ...*Error) *sql.DB
+	connectDbFunc   func(err ...*Error) (master, slave *sql.DB)
 	configPath      string
 	Config          Map
 	Db              HoTimeDB
@@ -157,7 +156,7 @@ func (this *Application) Run(router Router) {
 }
 
 //启动实例
-func (this *Application) SetConnectDB(connect func(err ...*Error) *sql.DB) {
+func (this *Application) SetConnectDB(connect func(err ...*Error) (master, slave *sql.DB)) {
 
 	this.connectDbFunc = connect
 	this.Db.SetConnect(this.connectDbFunc)
@@ -172,7 +171,7 @@ func (this *Application) SetSession(short CacheIns, Long CacheIns) {
 }
 
 //默认配置缓存和session实现
-func (this *Application) SetDefault(connect func(err ...*Error) *sql.DB) {
+func (this *Application) SetDefault(connect func(err ...*Error) (*sql.DB, *sql.DB)) {
 	this.SetConfig()
 
 	if connect != nil {
@@ -451,7 +450,7 @@ func Init(config string) Application {
 	appIns := Application{}
 	//手动模式，
 	appIns.SetConfig(config)
-	db.SetDB(&appIns)
+	SetDB(&appIns)
 	//appIns.SetCache()
 	return appIns
 }
diff --git a/db.go b/db.go
index 1bd52d5..fc32713 100644
--- a/db.go
+++ b/db.go
@@ -17,15 +17,15 @@ type HoTimeDB struct {
 	DBCached    bool
 	LastQuery   string
 	LastData    []interface{}
-	ConnectFunc func(err ...*Error) *sql.DB
+	ConnectFunc func(err ...*Error) (*sql.DB, *sql.DB)
 	LastErr     Error
 	limit       Slice
 	Tx          *sql.Tx //事务对象
-
+	SlaveDB     *sql.DB
 }
 
 //设置数据库配置连接
-func (this *HoTimeDB) SetConnect(connect func(err ...*Error) *sql.DB, err ...*Error) {
+func (this *HoTimeDB) SetConnect(connect func(err ...*Error) (master, slave *sql.DB), err ...*Error) {
 	this.ConnectFunc = connect
 	this.InitDb()
 }
@@ -55,15 +55,19 @@ func (this *HoTimeDB) InitDb(err ...*Error) Error {
 	if len(err) != 0 {
 		this.LastErr = *(err[0])
 	}
-	this.DB = this.ConnectFunc(&this.LastErr)
+	this.DB, this.SlaveDB = this.ConnectFunc(&this.LastErr)
 	if this.DB == nil {
-
 		return this.LastErr
 	}
 	e := this.DB.Ping()
 
 	this.LastErr.SetError(e)
 
+	if this.SlaveDB != nil {
+		e := this.SlaveDB.Ping()
+		this.LastErr.SetError(e)
+	}
+
 	return this.LastErr
 }
 
@@ -284,8 +288,13 @@ func (this *HoTimeDB) Query(query string, args ...interface{}) []Map {
 
 	this.LastQuery = query
 	this.LastData = args
+	//主从数据库切换，只有select语句有从数据库
+	db := this.DB
+	if this.SlaveDB != nil {
+		db = this.SlaveDB
+	}
 
-	if this.DB == nil {
+	if db == nil {
 		err = errors.New("没有初始化数据库")
 		this.LastErr.SetError(err)
 		return nil
@@ -294,12 +303,12 @@ func (this *HoTimeDB) Query(query string, args ...interface{}) []Map {
 	if this.Tx != nil {
 		resl, err = this.Tx.Query(query, args...)
 	} else {
-		resl, err = this.DB.Query(query, args...)
+		resl, err = db.Query(query, args...)
 	}
 
 	this.LastErr.SetError(err)
 	if err != nil {
-		if err = this.DB.Ping(); err != nil {
+		if err = db.Ping(); err != nil {
 			this.LastErr.SetError(err)
 			this.InitDb()
 			if this.LastErr.GetError() != nil {
diff --git a/db_assist.go b/db_assist.go
new file mode 100644
index 0000000..47519de
--- /dev/null
+++ b/db_assist.go
@@ -0,0 +1,58 @@
+package hotime
+
+import (
+	"database/sql"
+	_ "github.com/go-sql-driver/mysql"
+	_ "github.com/mattn/go-sqlite3"
+)
+
+func SetDB(appIns *Application) {
+	db := appIns.Config.GetMap("db")
+	dbSqlite := db.GetMap("sqlite")
+	dbMysql := db.GetMap("mysql")
+	if db != nil && dbSqlite != nil {
+		SetSqliteDB(appIns, dbSqlite)
+	}
+	if db != nil && dbMysql != nil {
+		SetMysqlDB(appIns, dbMysql)
+	}
+}
+func SetMysqlDB(appIns *Application, config Map) {
+	appIns.SetConnectDB(func(err ...*Error) (master, slave *sql.DB) {
+		//master数据库配置
+		query := config.GetString("user") + ":" + config.GetString("password") +
+			"@tcp(" + config.GetString("host") + ":" + config.GetString("port") + ")/" + config.GetString("name") + "?charset=utf8"
+		DB, e := sql.Open("mysql", query)
+		if e != nil && len(err) != 0 {
+			err[0].SetError(e)
+		}
+		master = DB
+		//slave数据库配置
+		configSlave := config.GetMap("slave")
+		if configSlave != nil {
+			query := configSlave.GetString("user") + ":" + configSlave.GetString("password") +
+				"@tcp(" + config.GetString("host") + ":" + configSlave.GetString("port") + ")/" + configSlave.GetString("name") + "?charset=utf8"
+			DB1, e := sql.Open("mysql", query)
+			if e != nil && len(err) != 0 {
+				err[0].SetError(e)
+			}
+			slave = DB1
+		}
+
+		return master, slave
+		//return DB
+	})
+	appIns.Db.Type = "mysql"
+}
+func SetSqliteDB(appIns *Application, config Map) {
+	appIns.SetConnectDB(func(err ...*Error) (master, slave *sql.DB) {
+		db, e := sql.Open("sqlite3", config.GetString("path"))
+		if e != nil && len(err) != 0 {
+			err[0].SetError(e)
+		}
+		master = db
+
+		return master, slave
+	})
+	appIns.Db.Type = "sqlite"
+}
diff --git a/example/main.go b/example/main.go
index b6591ce..da8bafd 100644
--- a/example/main.go
+++ b/example/main.go
@@ -2,7 +2,6 @@ package main
 
 import (
 	"../../hotime"
-	"../tools/db"
 	"database/sql"
 	"fmt"
 	//"go.hoteas.com/hotime/cache"
@@ -34,32 +33,19 @@ func main() {
 	//mysql
 	//mysql.SetDB(&appIns)
 	//自动选择数据库
-	db.SetDB(&appIns)
-
-	//appIns.SetConnectDB(func(err ...*hotime.Error) *sql.DB {
-	//	query := appIns.Config.GetString("dbUser") + ":" + appIns.Config.GetString("dbPwd") +
-	//		"@tcp(" + appIns.Config.GetString("dbHost") + ":" + appIns.Config.GetString("dbPort") + ")/" + appIns.Config.GetString("dbName") + "?charset=utf8"
-	//	DB, e := sql.Open("mysql", query)
-	//	if e != nil && len(err) != 0 {
-	//		err[0].SetError(e)
-	//	}
-	//	return DB
-	//})
-	//内存缓存数据库数据，错误则删除
-	//	appIns.Db.CacheIns=hotime.CacheIns(&hotime.CacheMemory{})
 
 	appIns.SetSession(hotime.CacheIns(&hotime.CacheMemory{}), hotime.CacheIns(&hotime.CacheDb{Db: &appIns.Db, Time: appIns.Config.GetInt64("cacheTime")}))
 	appIns.SetCache(hotime.CacheIns(&hotime.CacheMemory{}))
 
 	//快捷模式
-	appIns.SetDefault(func(err ...*hotime.Error) *sql.DB {
+	appIns.SetDefault(func(err ...*hotime.Error) (*sql.DB, *sql.DB) {
 		query := appIns.Config.GetString("dbUser") + ":" + appIns.Config.GetString("dbPwd") +
 			"@tcp(" + appIns.Config.GetString("dbHost") + ":" + appIns.Config.GetString("dbPort") + ")/" + appIns.Config.GetString("dbName") + "?charset=utf8"
 		DB, e := sql.Open("mysql", query)
 		if e != nil && len(err) != 0 {
 			err[0].SetError(e)
 		}
-		return DB
+		return DB, nil
 	})
 
 	appIns.Run(hotime.Router{
diff --git a/tools/db/auto.go b/tools/db/auto.go
deleted file mode 100644
index 059bbcd..0000000
--- a/tools/db/auto.go
+++ /dev/null
@@ -1,19 +0,0 @@
-package db
-
-import (
-	"../../../hotime"
-	"../mysql"
-	"../sqlite"
-)
-
-func SetDB(appIns *hotime.Application) {
-	db := appIns.Config.GetMap("db")
-	dbSqlite := db.GetMap("sqlite")
-	dbMysql := db.GetMap("mysql")
-	if db != nil && dbSqlite != nil {
-		sqlite.SetDB(appIns, dbSqlite)
-	}
-	if db != nil && dbMysql != nil {
-		mysql.SetDB(appIns, dbMysql)
-	}
-}
diff --git a/tools/mysql/mysql.go b/tools/mysql/mysql.go
deleted file mode 100644
index 3e420fa..0000000
--- a/tools/mysql/mysql.go
+++ /dev/null
@@ -1,20 +0,0 @@
-package mysql
-
-import (
-	"../../../hotime"
-	"database/sql"
-	_ "github.com/go-sql-driver/mysql"
-)
-
-func SetDB(appIns *hotime.Application, config hotime.Map) {
-	appIns.SetConnectDB(func(err ...*hotime.Error) *sql.DB {
-		query := config.GetString("user") + ":" + config.GetString("password") +
-			"@tcp(" + config.GetString("host") + ":" + config.GetString("port") + ")/" + config.GetString("name") + "?charset=utf8"
-		DB, e := sql.Open("mysql", query)
-		if e != nil && len(err) != 0 {
-			err[0].SetError(e)
-		}
-		return DB
-	})
-	appIns.Db.Type = "mysql"
-}
diff --git a/tools/sqlite/sqlite.go b/tools/sqlite/sqlite.go
deleted file mode 100644
index 69786c6..0000000
--- a/tools/sqlite/sqlite.go
+++ /dev/null
@@ -1,18 +0,0 @@
-package sqlite
-
-import (
-	"../../../hotime"
-	"database/sql"
-	_ "github.com/mattn/go-sqlite3"
-)
-
-func SetDB(appIns *hotime.Application, config hotime.Map) {
-	appIns.SetConnectDB(func(err ...*hotime.Error) *sql.DB {
-		db, e := sql.Open("sqlite3", config.GetString("path"))
-		if e != nil && len(err) != 0 {
-			err[0].SetError(e)
-		}
-		return db
-	})
-	appIns.Db.Type = "sqlite"
-}