diff --git a/base_test.go b/base_test.go
index 2c12c6d3..c17ed772 100644
--- a/base_test.go
+++ b/base_test.go
@@ -42,7 +42,7 @@ type Userdetail struct {
 }
 
 func directCreateTable(engine *Engine, t *testing.T) {
-	err := engine.CreateTables(&Userinfo{})
+	err := engine.Sync(&Userinfo{})
 	if err != nil {
 		t.Error(err)
 		panic(err)
diff --git a/benchmark_base_test.go b/benchmark_base_test.go
new file mode 100644
index 00000000..89c2a80e
--- /dev/null
+++ b/benchmark_base_test.go
@@ -0,0 +1,50 @@
+package xorm
+
+import (
+	"testing"
+)
+
+type BigStruct struct {
+	Id       int64
+	Name     string
+	Title    string
+	Age      string
+	Alias    string
+	NickName string
+}
+
+func doBenchCacheFind(engine *Engine, b *testing.B) {
+	b.StopTimer()
+	bs := &BigStruct{0, "fafdasf", "fadfa", "afadfsaf", "fadfafdsafd", "fadfafdsaf"}
+	err := engine.CreateTables(bs)
+	if err != nil {
+		b.Error(err)
+		return
+	}
+
+	for i := 0; i < 100; i++ {
+		bs.Id = 0
+		_, err = engine.Insert(bs)
+		if err != nil {
+			b.Error(err)
+			return
+		}
+	}
+
+	b.StartTimer()
+	for i := 0; i < b.N; i++ {
+		bss := new([]BigStruct)
+		err = engine.Limit(50).Find(bss)
+		if err != nil {
+			b.Error(err)
+			return
+		}
+	}
+	b.StopTimer()
+	err = engine.DropTables(bs)
+	if err != nil {
+		b.Error(err)
+		return
+	}
+
+}
diff --git a/engine.go b/engine.go
index 9fea8bcd..c006b33c 100644
--- a/engine.go
+++ b/engine.go
@@ -2,6 +2,7 @@ package xorm
 
 import (
 	"database/sql"
+	"errors"
 	"fmt"
 	"io"
 	"reflect"
@@ -18,6 +19,7 @@ const (
 )
 
 type dialect interface {
+	Init(uri string) error
 	SqlType(t *Column) string
 	SupportInsertMany() bool
 	QuoteStr() string
@@ -25,6 +27,9 @@ type dialect interface {
 	SupportEngine() bool
 	SupportCharset() bool
 	IndexOnTable() bool
+	IndexCheckSql(tableName, idxName string) (string, []interface{})
+	TableCheckSql(tableName string) (string, []interface{})
+	ColumnCheckSql(tableName, colName string) (string, []interface{})
 }
 
 type Engine struct {
@@ -70,6 +75,7 @@ func (engine *Engine) SetPool(pool IConnectPool) error {
 	return engine.Pool.Init(engine)
 }
 
+// only for go 1.2+
 func (engine *Engine) SetMaxConns(conns int) {
 	engine.Pool.SetMaxConns(conns)
 }
@@ -465,6 +471,132 @@ func (engine *Engine) Map(beans ...interface{}) (e error) {
 	return
 }
 
+// is a table has
+func (engine *Engine) IsEmptyTable(bean interface{}) (bool, error) {
+	t := Type(bean)
+	if t.Kind() != reflect.Struct {
+		return false, errors.New("bean should be a struct or struct's point")
+	}
+	engine.AutoMapType(t)
+	session := engine.NewSession()
+	defer session.Close()
+	has, err := session.Get(bean)
+	return !has, err
+}
+
+func (engine *Engine) isTableExist(bean interface{}) (bool, error) {
+	t := Type(bean)
+	if t.Kind() != reflect.Struct {
+		return false, errors.New("bean should be a struct or struct's point")
+	}
+	table := engine.AutoMapType(t)
+	session := engine.NewSession()
+	defer session.Close()
+	has, err := session.isTableExist(table.Name)
+	return has, err
+}
+
+func (engine *Engine) ClearCache(beans ...interface{}) {
+	for _, bean := range beans {
+		table := engine.AutoMap(bean)
+		table.Cacher.ClearIds(table.Name)
+	}
+}
+
+// sync the new struct to database, this method will auto add column, index, unique
+// but will not delete or change anything.
+func (engine *Engine) Sync(beans ...interface{}) error {
+	for _, bean := range beans {
+		table := engine.AutoMap(bean)
+
+		s := engine.NewSession()
+		defer s.Close()
+		isExist, err := s.Table(bean).isTableExist(table.Name)
+		if err != nil {
+			return err
+		}
+		if !isExist {
+			err = engine.CreateTables(bean)
+			if err != nil {
+				return err
+			}
+		} else {
+			isEmpty, err := engine.IsEmptyTable(bean)
+			if err != nil {
+				return err
+			}
+			if isEmpty {
+				err = engine.DropTables(bean)
+				if err != nil {
+					return err
+				}
+				err = engine.CreateTables(bean)
+				if err != nil {
+					return err
+				}
+			} else {
+				for _, col := range table.Columns {
+					session := engine.NewSession()
+					session.Statement.RefTable = table
+					defer session.Close()
+					isExist, err := session.isColumnExist(table.Name, col.Name)
+					if err != nil {
+						return err
+					}
+					if !isExist {
+						session := engine.NewSession()
+						session.Statement.RefTable = table
+						defer session.Close()
+						err = session.addColumn(col.Name)
+						if err != nil {
+							return err
+						}
+					}
+				}
+
+				for idx, _ := range table.Indexes {
+					session := engine.NewSession()
+					session.Statement.RefTable = table
+					defer session.Close()
+					isExist, err := session.isIndexExist(table.Name, idx, false)
+					if err != nil {
+						return err
+					}
+					if !isExist {
+						session := engine.NewSession()
+						session.Statement.RefTable = table
+						defer session.Close()
+						err = session.addIndex(table.Name, idx)
+						if err != nil {
+							return err
+						}
+					}
+				}
+
+				for uqe, _ := range table.Uniques {
+					session := engine.NewSession()
+					session.Statement.RefTable = table
+					defer session.Close()
+					isExist, err := session.isIndexExist(table.Name, uqe, true)
+					if err != nil {
+						return err
+					}
+					if !isExist {
+						session := engine.NewSession()
+						session.Statement.RefTable = table
+						defer session.Close()
+						err = session.addUnique(table.Name, uqe)
+						if err != nil {
+							return err
+						}
+					}
+				}
+			}
+		}
+	}
+	return nil
+}
+
 func (engine *Engine) UnMap(beans ...interface{}) (e error) {
 	engine.mutex.Lock()
 	defer engine.mutex.Unlock()
diff --git a/examples/sync.go b/examples/sync.go
new file mode 100644
index 00000000..aad010d9
--- /dev/null
+++ b/examples/sync.go
@@ -0,0 +1,64 @@
+package main
+
+import (
+	"fmt"
+	_ "github.com/bylevel/pq"
+	_ "github.com/go-sql-driver/mysql"
+	_ "github.com/mattn/go-sqlite3"
+	"xorm"
+)
+
+type SyncUser struct {
+	Id   int64
+	Name string `xorm:"unique"`
+	Age  int    `xorm:"index"`
+}
+
+type SyncLoginInfo struct {
+	Id       int64
+	IP       string `xorm:"index"`
+	UserId   int64
+	AddedCol int
+	// timestamp should be updated by database, so only allow get from db
+	TimeStamp string
+	// assume
+	Nonuse int
+}
+
+func sync(engine *xorm.Engine) error {
+	return engine.Sync(&SyncLoginInfo{}, &SyncUser{})
+}
+
+func sqliteEngine() (*xorm.Engine, error) {
+	f := "sync.db"
+	//os.Remove(f)
+
+	return xorm.NewEngine("sqlite3", f)
+}
+
+func mysqlEngine() (*xorm.Engine, error) {
+	return xorm.NewEngine("mysql", "root:@/test?charset=utf8")
+}
+
+func postgresEngine() (*xorm.Engine, error) {
+	return xorm.NewEngine("postgres", "dbname=xorm_test sslmode=disable")
+}
+
+type engineFunc func() (*xorm.Engine, error)
+
+func main() {
+	engines := []engineFunc{sqliteEngine, mysqlEngine, postgresEngine}
+	for _, enginefunc := range engines {
+		Orm, err := enginefunc()
+		fmt.Println("--------", Orm.DriverName, "----------")
+		if err != nil {
+			fmt.Println(err)
+			return
+		}
+		Orm.ShowSQL = true
+		err = sync(Orm)
+		if err != nil {
+			fmt.Println(err)
+		}
+	}
+}
diff --git a/filter.go b/filter.go
index ec46aa8b..dcf1aac9 100644
--- a/filter.go
+++ b/filter.go
@@ -25,10 +25,10 @@ func (s *PgSeqFilter) Do(sql string, session *Session) string {
 	return res
 }
 
-type PgQuoteFilter struct {
+type QuoteFilter struct {
 }
 
-func (s *PgQuoteFilter) Do(sql string, session *Session) string {
+func (s *QuoteFilter) Do(sql string, session *Session) string {
 	return strings.Replace(sql, "`", session.Engine.QuoteStr(), -1)
 }
 
diff --git a/mymysql.go b/mymysql.go
new file mode 100644
index 00000000..d9317c2f
--- /dev/null
+++ b/mymysql.go
@@ -0,0 +1,65 @@
+package xorm
+
+import (
+	"errors"
+	"strings"
+	"time"
+)
+
+type mymysql struct {
+	mysql
+	proto   string
+	raddr   string
+	laddr   string
+	timeout time.Duration
+	db      string
+	user    string
+	passwd  string
+}
+
+func (db *mymysql) Init(uri string) error {
+	pd := strings.SplitN(uri, "*", 2)
+	if len(pd) == 2 {
+		// Parse protocol part of URI
+		p := strings.SplitN(pd[0], ":", 2)
+		if len(p) != 2 {
+			return errors.New("Wrong protocol part of URI")
+		}
+		db.proto = p[0]
+		options := strings.Split(p[1], ",")
+		db.raddr = options[0]
+		for _, o := range options[1:] {
+			kv := strings.SplitN(o, "=", 2)
+			var k, v string
+			if len(kv) == 2 {
+				k, v = kv[0], kv[1]
+			} else {
+				k, v = o, "true"
+			}
+			switch k {
+			case "laddr":
+				db.laddr = v
+			case "timeout":
+				to, err := time.ParseDuration(v)
+				if err != nil {
+					return err
+				}
+				db.timeout = to
+			default:
+				return errors.New("Unknown option: " + k)
+			}
+		}
+		// Remove protocol part
+		pd = pd[1:]
+	}
+	// Parse database part of URI
+	dup := strings.SplitN(pd[0], "/", 3)
+	if len(dup) != 3 {
+		return errors.New("Wrong database part of URI")
+	}
+	db.dbname = dup[0]
+	db.user = dup[1]
+	db.passwd = dup[2]
+
+	return nil
+}
diff --git a/mymysql_test.go b/mymysql_test.go
index 17e5bc70..cbc951bd 100644
--- a/mymysql_test.go
+++ b/mymysql_test.go
@@ -10,6 +10,8 @@ CREATE DATABASE IF NOT EXISTS xorm_test CHARACTER SET
 utf8 COLLATE utf8_general_ci;
 */
 
+var showTestSql bool = false
+
 func TestMyMysql(t *testing.T) {
 	engine, err := NewEngine("mymysql", "xorm_test2/root/")
 	defer engine.Close()
@@ -17,8 +19,30 @@ func TestMyMysql(t *testing.T) {
 		t.Error(err)
 		return
 	}
-	engine.ShowSQL = true
+	engine.ShowSQL = showTestSql
 
 	testAll(engine, t)
 	testAll2(engine, t)
 }
+
+func BenchmarkMyMysqlNoCache(t *testing.B) {
+	engine, err := NewEngine("mymysql", "xorm_test2/root/")
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	//engine.ShowSQL = true
+	doBenchCacheFind(engine, t)
+}
+
+func BenchmarkMyMysqlCache(t *testing.B) {
+	engine, err := NewEngine("mymysql", "xorm_test2/root/")
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	engine.SetDefaultCacher(NewLRUCacher(NewMemoryStore(), 1000))
+	doBenchCacheFind(engine, t)
+}
diff --git a/mysql.go b/mysql.go
index fdddfd2d..080920cc 100644
--- a/mysql.go
+++ b/mysql.go
@@ -1,10 +1,63 @@
 package xorm
 
 import (
+	"crypto/tls"
+	//"fmt"
+	"regexp"
 	"strconv"
+	//"strings"
+	"time"
 )
 
 type mysql struct {
+	user              string
+	passwd            string
+	net               string
+	addr              string
+	dbname            string
+	params            map[string]string
+	loc               *time.Location
+	timeout           time.Duration
+	tls               *tls.Config
+	allowAllFiles     bool
+	allowOldPasswords bool
+	clientFoundRows   bool
+}
+
+/*func readBool(input string) (value bool, valid bool) {
+	switch input {
+	case "1", "true", "TRUE", "True":
+		return true, true
+	case "0", "false", "FALSE", "False":
+		return false, true
+	}
+
+	// Not a valid bool value
+	return
+}*/
+
+func (cfg *mysql) parseDSN(dsn string) (err error) {
+	//cfg.params = make(map[string]string)
+	dsnPattern := regexp.MustCompile(
+		`^(?:(?P<user>.*?)(?::(?P<passwd>.*))?@)?` + // [user[:password]@]
+			`(?:(?P<net>[^\(]*)(?:\((?P<addr>[^\)]*)\))?)?` + // [net[(addr)]]
+			`\/(?P<dbname>.*?)` + // /dbname
+			`(?:\?(?P<params>[^\?]*))?$`) // [?param1=value1&paramN=valueN]
+	matches := dsnPattern.FindStringSubmatch(dsn)
+	//tlsConfigRegister := make(map[string]*tls.Config)
+	names := dsnPattern.SubexpNames()
+
+	for i, match := range matches {
+		switch names[i] {
+		case "dbname":
+			cfg.dbname = match
+		}
+	}
+	return
+}
+
+func (db *mysql) Init(uri string) error {
+	return db.parseDSN(uri)
 }
 
 func (db *mysql) SqlType(c *Column) string {
@@ -46,14 +99,14 @@ func (db *mysql) QuoteStr() string {
 	return "`"
 }
 
-func (db *mysql) AutoIncrStr() string {
-	return "AUTO_INCREMENT"
-}
-
 func (db *mysql) SupportEngine() bool {
 	return true
 }
 
+func (db *mysql) AutoIncrStr() string {
+	return "AUTO_INCREMENT"
+}
+
 func (db *mysql) SupportCharset() bool {
 	return true
 }
@@ -61,3 +114,22 @@ func (db *mysql) SupportCharset() bool {
 func (db *mysql) IndexOnTable() bool {
 	return true
 }
+
+func (db *mysql) IndexCheckSql(tableName, idxName string) (string, []interface{}) {
+	args := []interface{}{db.dbname, tableName, idxName}
+	sql := "SELECT `INDEX_NAME` FROM `INFORMATION_SCHEMA`.`STATISTICS`"
+	sql += " WHERE `TABLE_SCHEMA` = ? AND `TABLE_NAME` = ? AND `INDEX_NAME`=?"
+	return sql, args
+}
+
+func (db *mysql) ColumnCheckSql(tableName, colName string) (string, []interface{}) {
+	args := []interface{}{db.dbname, tableName, colName}
+	sql := "SELECT `COLUMN_NAME` FROM `INFORMATION_SCHEMA`.`COLUMNS` WHERE `TABLE_SCHEMA` = ? AND `TABLE_NAME` = ? AND `COLUMN_NAME` = ?"
+	return sql, args
+}
+
+func (db *mysql) TableCheckSql(tableName string) (string, []interface{}) {
+	args := []interface{}{db.dbname, tableName}
+	sql := "SELECT `TABLE_NAME` from `INFORMATION_SCHEMA`.`TABLES` WHERE `TABLE_SCHEMA`=? and `TABLE_NAME`=?"
+	return sql, args
+}
diff --git a/mysql_test.go b/mysql_test.go
index 085144ac..adb04f1c 100644
--- a/mysql_test.go
+++ b/mysql_test.go
@@ -17,8 +17,30 @@ func TestMysql(t *testing.T) {
 		t.Error(err)
 		return
 	}
-	engine.ShowSQL = true
+	engine.ShowSQL = showTestSql
 
 	testAll(engine, t)
 	testAll2(engine, t)
 }
+
+func BenchmarkMysqlNoCache(t *testing.B) {
+	engine, err := NewEngine("mysql", "root:@/xorm_test?charset=utf8")
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	//engine.ShowSQL = true
+	doBenchCacheFind(engine, t)
+}
+
+func BenchmarkMysqlCache(t *testing.B) {
+	engine, err := NewEngine("mysql", "root:@/xorm_test?charset=utf8")
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	engine.SetDefaultCacher(NewLRUCacher(NewMemoryStore(), 1000))
+	doBenchCacheFind(engine, t)
+}
diff --git a/postgres.go b/postgres.go
index 1287dfc6..88b6831e 100644
--- a/postgres.go
+++ b/postgres.go
@@ -1,8 +1,58 @@
 package xorm
 
-import "strconv"
+import (
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+)
 
 type postgres struct {
+	dbname string
+}
+
+type Values map[string]string
+
+func (vs Values) Set(k, v string) {
+	vs[k] = v
+}
+
+func (vs Values) Get(k string) (v string) {
+	return vs[k]
+}
+
+type Error error
+
+func errorf(s string, args ...interface{}) {
+	panic(Error(fmt.Errorf("pq: %s", fmt.Sprintf(s, args...))))
+}
+
+func parseOpts(name string, o Values) {
+	if len(name) == 0 {
+		return
+	}
+
+	name = strings.TrimSpace(name)
+
+	ps := strings.Split(name, " ")
+	for _, p := range ps {
+		kv := strings.Split(p, "=")
+		if len(kv) < 2 {
+			errorf("invalid option: %q", p)
+		}
+		o.Set(kv[0], kv[1])
+	}
+}
+
+func (db *postgres) Init(uri string) error {
+	o := make(Values)
+	parseOpts(uri, o)
+
+	db.dbname = o.Get("dbname")
+	if db.dbname == "" {
+		return errors.New("dbname is empty")
+	}
+	return nil
 }
 
 func (db *postgres) SqlType(c *Column) string {
@@ -68,3 +118,20 @@ func (db *postgres) SupportCharset() bool {
 func (db *postgres) IndexOnTable() bool {
 	return false
 }
+
+func (db *postgres) IndexCheckSql(tableName, idxName string) (string, []interface{}) {
+	args := []interface{}{tableName, idxName}
+	return `SELECT indexname FROM pg_indexes ` +
+		`WHERE tablename = ? AND indexname = ?`, args
+}
+
+func (db *postgres) TableCheckSql(tableName string) (string, []interface{}) {
+	args := []interface{}{tableName}
+	return `SELECT tablename FROM pg_tables WHERE tablename = ?`, args
+}
+
+func (db *postgres) ColumnCheckSql(tableName, colName string) (string, []interface{}) {
+	args := []interface{}{tableName, colName}
+	return "SELECT column_name FROM INFORMATION_SCHEMA.COLUMNS WHERE table_name = ?" +
+		" AND column_name = ?", args
+}
diff --git a/postgres_test.go b/postgres_test.go
index 7aa72d69..cac0719f 100644
--- a/postgres_test.go
+++ b/postgres_test.go
@@ -13,7 +13,7 @@ func TestPostgres(t *testing.T) {
 		return
 	}
 	defer engine.Close()
-	engine.ShowSQL = true
+	engine.ShowSQL = showTestSql
 
 	testAll(engine, t)
 	testAll2(engine, t)
@@ -26,7 +26,7 @@ func TestPostgres2(t *testing.T) {
 		return
 	}
 	defer engine.Close()
-	engine.ShowSQL = true
+	engine.ShowSQL = showTestSql
 	engine.Mapper = SameMapper{}
 
 	fmt.Println("-------------- directCreateTable --------------")
@@ -98,3 +98,27 @@ func TestPostgres2(t *testing.T) {
 	fmt.Println("-------------- testIndexAndUnique --------------")
 	testIndexAndUnique(engine, t)
 }
+
+func BenchmarkPostgresNoCache(t *testing.B) {
+	engine, err := NewEngine("postgres", "dbname=xorm_test sslmode=disable")
+
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	//engine.ShowSQL = true
+	doBenchCacheFind(engine, t)
+}
+
+func BenchmarkPostgresCache(t *testing.B) {
+	engine, err := NewEngine("postgres", "dbname=xorm_test sslmode=disable")
+
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	engine.SetDefaultCacher(NewLRUCacher(NewMemoryStore(), 1000))
+	doBenchCacheFind(engine, t)
+}
diff --git a/session.go b/session.go
index 3128d4fa..f44f0fc6 100644
--- a/session.go
+++ b/session.go
@@ -293,27 +293,53 @@ func (session *Session) CreateTable(bean interface{}) error {
 	return session.createOneTable()
 }
 
+func (session *Session) CreateIndexes(bean interface{}) error {
+	session.Statement.RefTable = session.Engine.AutoMap(bean)
+
+	err := session.newDb()
+	if err != nil {
+		return err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+
+	sqls := session.Statement.genIndexSQL()
+	for _, sql := range sqls {
+		_, err = session.exec(sql)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (session *Session) CreateUniques(bean interface{}) error {
+	session.Statement.RefTable = session.Engine.AutoMap(bean)
+
+	err := session.newDb()
+	if err != nil {
+		return err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+
+	sqls := session.Statement.genUniqueSQL()
+	for _, sql := range sqls {
+		_, err = session.exec(sql)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (session *Session) createOneTable() error {
 	sql := session.Statement.genCreateSQL()
 	_, err := session.exec(sql)
-	if err == nil {
-		sqls := session.Statement.genIndexSQL()
-		for _, sql := range sqls {
-			_, err = session.exec(sql)
-			if err != nil {
-				return err
-			}
-		}
-	}
-	if err == nil {
-		sqls := session.Statement.genUniqueSQL()
-		for _, sql := range sqls {
-			_, err = session.exec(sql)
-			if err != nil {
-				return err
-			}
-		}
-	}
 	return err
 }
 
@@ -337,6 +363,26 @@ func (session *Session) CreateAll() error {
 	return nil
 }
 
+func (session *Session) DropIndexes(bean interface{}) error {
+	err := session.newDb()
+	if err != nil {
+		return err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+
+	sqls := session.Statement.genDelIndexSQL()
+	for _, sql := range sqls {
+		_, err = session.exec(sql)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 // DropTable drop a table and all indexes of the table
 func (session *Session) DropTable(bean interface{}) error {
 	err := session.newDb()
@@ -355,14 +401,6 @@ func (session *Session) DropTable(bean interface{}) error {
 		session.Statement.AltTableName = bean.(string)
 	} else if t.Kind() == reflect.Struct {
 		session.Statement.RefTable = session.Engine.AutoMap(bean)
-
-		sqls := session.Statement.genDelIndexSQL()
-		for _, sql := range sqls {
-			_, err = session.exec(sql)
-			if err != nil {
-				return err
-			}
-		}
 	} else {
 		return errors.New("Unsupported type")
 	}
@@ -727,6 +765,7 @@ func (session *Session) Find(rowsSlicePtr interface{}, condiBean ...interface{})
 	return nil
 }
 
+// test if database is ok
 func (session *Session) Ping() error {
 	err := session.newDb()
 	if err != nil {
@@ -740,6 +779,102 @@ func (session *Session) Ping() error {
 	return session.Db.Ping()
 }
 
+func (session *Session) isColumnExist(tableName, colName string) (bool, error) {
+	err := session.newDb()
+	if err != nil {
+		return false, err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+	sql, args := session.Engine.Dialect.ColumnCheckSql(tableName, colName)
+	results, err := session.query(sql, args...)
+	return len(results) > 0, err
+}
+
+func (session *Session) isTableExist(tableName string) (bool, error) {
+	err := session.newDb()
+	if err != nil {
+		return false, err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+	sql, args := session.Engine.Dialect.TableCheckSql(tableName)
+	results, err := session.query(sql, args...)
+	return len(results) > 0, err
+}
+
+func (session *Session) isIndexExist(tableName, idxName string, unique bool) (bool, error) {
+	err := session.newDb()
+	if err != nil {
+		return false, err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+	var idx string
+	if unique {
+		idx = uniqueName(tableName, idxName)
+	} else {
+		idx = indexName(tableName, idxName)
+	}
+	sql, args := session.Engine.Dialect.IndexCheckSql(tableName, idx)
+	results, err := session.query(sql, args...)
+	return len(results) > 0, err
+}
+
+func (session *Session) addColumn(colName string) error {
+	err := session.newDb()
+	if err != nil {
+		return err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+	//fmt.Println(session.Statement.RefTable)
+	col := session.Statement.RefTable.Columns[colName]
+	sql, args := session.Statement.genAddColumnStr(col)
+	_, err = session.exec(sql, args...)
+	return err
+}
+
+func (session *Session) addIndex(tableName, idxName string) error {
+	err := session.newDb()
+	if err != nil {
+		return err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+	//fmt.Println(idxName)
+	cols := session.Statement.RefTable.Indexes[idxName]
+	sql, args := session.Statement.genAddIndexStr(indexName(tableName, idxName), cols)
+	_, err = session.exec(sql, args...)
+	return err
+}
+
+func (session *Session) addUnique(tableName, uqeName string) error {
+	err := session.newDb()
+	if err != nil {
+		return err
+	}
+	defer session.Statement.Init()
+	if session.IsAutoClose {
+		defer session.Close()
+	}
+	//fmt.Println(uqeName, session.Statement.RefTable.Uniques)
+	cols := session.Statement.RefTable.Uniques[uqeName]
+	sql, args := session.Statement.genAddUniqueStr(uniqueName(tableName, uqeName), cols)
+	_, err = session.exec(sql, args...)
+	return err
+}
+
 func (session *Session) DropAll() error {
 	err := session.newDb()
 	if err != nil {
diff --git a/sqlite3.go b/sqlite3.go
index 525e8ebc..1d464524 100644
--- a/sqlite3.go
+++ b/sqlite3.go
@@ -3,6 +3,10 @@ package xorm
 type sqlite3 struct {
 }
 
+func (db *sqlite3) Init(uri string) error {
+	return nil
+}
+
 func (db *sqlite3) SqlType(c *Column) string {
 	switch t := c.SQLType.Name; t {
 	case Date, DateTime, TimeStamp, Time:
@@ -50,3 +54,18 @@ func (db *sqlite3) SupportCharset() bool {
 func (db *sqlite3) IndexOnTable() bool {
 	return false
 }
+
+func (db *sqlite3) IndexCheckSql(tableName, idxName string) (string, []interface{}) {
+	args := []interface{}{idxName}
+	return "SELECT name FROM sqlite_master WHERE type='index' and name = ?", args
+}
+
+func (db *sqlite3) TableCheckSql(tableName string) (string, []interface{}) {
+	args := []interface{}{tableName}
+	return "SELECT name FROM sqlite_master WHERE type='table' and name = ?", args
+}
+
+func (db *sqlite3) ColumnCheckSql(tableName, colName string) (string, []interface{}) {
+	args := []interface{}{tableName}
+	return "SELECT name FROM sqlite_master WHERE type='table' and name = ? and sql like '%`" + colName + "`%'", args
+}
diff --git a/sqlite3_test.go b/sqlite3_test.go
index 5c7f3de9..0a1c33a8 100644
--- a/sqlite3_test.go
+++ b/sqlite3_test.go
@@ -14,8 +14,32 @@ func TestSqlite3(t *testing.T) {
 		t.Error(err)
 		return
 	}
-	engine.ShowSQL = true
+	engine.ShowSQL = showTestSql
 
 	testAll(engine, t)
 	testAll2(engine, t)
 }
+
+func BenchmarkSqlite3NoCache(t *testing.B) {
+	os.Remove("./test.db")
+	engine, err := NewEngine("sqlite3", "./test.db")
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	//engine.ShowSQL = true
+	doBenchCacheFind(engine, t)
+}
+
+func BenchmarkSqlite3Cache(t *testing.B) {
+	os.Remove("./test.db")
+	engine, err := NewEngine("sqlite3", "./test.db")
+	defer engine.Close()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	engine.SetDefaultCacher(NewLRUCacher(NewMemoryStore(), 1000))
+	doBenchCacheFind(engine, t)
+}
diff --git a/statement.go b/statement.go
index d23b5757..e21467ca 100644
--- a/statement.go
+++ b/statement.go
@@ -279,47 +279,57 @@ func (statement *Statement) genCreateSQL() string {
 	return sql
 }
 
-func (statement *Statement) genIndexSQL() []string {
+func indexName(tableName, idxName string) string {
+	return fmt.Sprintf("IDX_%v_%v", tableName, idxName)
+}
+
+func (s *Statement) genIndexSQL() []string {
 	var sqls []string = make([]string, 0)
-	for indexName, cols := range statement.RefTable.Indexes {
-		sql := fmt.Sprintf("CREATE INDEX IDX_%v_%v ON %v (%v);", statement.TableName(), indexName,
-			statement.Engine.Quote(statement.TableName()), statement.Engine.Quote(strings.Join(cols, statement.Engine.Quote(","))))
+	tbName := s.TableName()
+	quote := s.Engine.Quote
+	for idxName, cols := range s.RefTable.Indexes {
+		sql := fmt.Sprintf("CREATE INDEX %v ON %v (%v);", quote(indexName(tbName, idxName)),
+			quote(tbName), quote(strings.Join(cols, quote(","))))
 		sqls = append(sqls, sql)
 	}
 	return sqls
 }
 
+func uniqueName(tableName, uqeName string) string {
+	return fmt.Sprintf("UQE_%v_%v", tableName, uqeName)
+}
+
 func (statement *Statement) genUniqueSQL() []string {
 	var sqls []string = make([]string, 0)
 	for indexName, cols := range statement.RefTable.Uniques {
-		sql := fmt.Sprintf("CREATE UNIQUE INDEX `UQE_%v_%v` ON %v (%v);", statement.TableName(), indexName,
+		sql := fmt.Sprintf("CREATE UNIQUE INDEX `%v` ON %v (%v);", uniqueName(statement.TableName(), indexName),
 			statement.Engine.Quote(statement.TableName()), statement.Engine.Quote(strings.Join(cols, statement.Engine.Quote(","))))
 		sqls = append(sqls, sql)
 	}
 	return sqls
 }
 
-func (statement *Statement) genDelIndexSQL() []string {
+func (s *Statement) genDelIndexSQL() []string {
 	var sqls []string = make([]string, 0)
-	for indexName, _ := range statement.RefTable.Uniques {
-		sql := fmt.Sprintf("DROP INDEX `UQE_%v_%v`", statement.TableName(), indexName)
-		if statement.Engine.Dialect.IndexOnTable() {
-			sql += fmt.Sprintf(" ON %v", statement.Engine.Quote(statement.TableName()))
+	for indexName, _ := range s.RefTable.Uniques {
+		sql := fmt.Sprintf("DROP INDEX %v", s.Engine.Quote(uniqueName(s.TableName(), indexName)))
+		if s.Engine.Dialect.IndexOnTable() {
+			sql += fmt.Sprintf(" ON %v", s.Engine.Quote(s.TableName()))
 		}
 		sqls = append(sqls, sql)
 	}
-	for indexName, _ := range statement.RefTable.Indexes {
-		sql := fmt.Sprintf("DROP INDEX IDX_%v_%v", statement.TableName(), indexName)
-		if statement.Engine.Dialect.IndexOnTable() {
-			sql += fmt.Sprintf(" ON %v", statement.Engine.Quote(statement.TableName()))
+	for indexName, _ := range s.RefTable.Indexes {
+		sql := fmt.Sprintf("DROP INDEX %v", s.Engine.Quote(uniqueName(s.TableName(), indexName)))
+		if s.Engine.Dialect.IndexOnTable() {
+			sql += fmt.Sprintf(" ON %v", s.Engine.Quote(s.TableName()))
 		}
 		sqls = append(sqls, sql)
 	}
 	return sqls
 }
 
-func (statement *Statement) genDropSQL() string {
-	sql := "DROP TABLE IF EXISTS " + statement.Engine.Quote(statement.TableName()) + ";"
+func (s *Statement) genDropSQL() string {
+	sql := "DROP TABLE IF EXISTS " + s.Engine.Quote(s.TableName()) + ";"
 	return sql
 }
 
@@ -339,6 +349,27 @@ func (statement Statement) genGetSql(bean interface{}) (string, []interface{}) {
 	return statement.genSelectSql(columnStr), append(statement.Params, statement.BeanArgs...)
 }
 
+func (s *Statement) genAddColumnStr(col *Column) (string, []interface{}) {
+	quote := s.Engine.Quote
+	sql := fmt.Sprintf("ALTER TABLE %v ADD COLUMN %v;", quote(s.TableName()),
+		col.String(s.Engine))
+	return sql, []interface{}{}
+}
+
+func (s *Statement) genAddIndexStr(idxName string, cols []string) (string, []interface{}) {
+	quote := s.Engine.Quote
+	colstr := quote(strings.Join(cols, quote(", ")))
+	sql := fmt.Sprintf("CREATE INDEX %v ON %v (%v);", quote(idxName), quote(s.TableName()), colstr)
+	return sql, []interface{}{}
+}
+
+func (s *Statement) genAddUniqueStr(uqeName string, cols []string) (string, []interface{}) {
+	quote := s.Engine.Quote
+	colstr := quote(strings.Join(cols, quote(", ")))
+	sql := fmt.Sprintf("CREATE UNIQUE INDEX %v ON %v (%v);", quote(uqeName), quote(s.TableName()), colstr)
+	return sql, []interface{}{}
+}
+
 func (statement Statement) genCountSql(bean interface{}) (string, []interface{}) {
 	table := statement.Engine.AutoMap(bean)
 	statement.RefTable = table
diff --git a/table.go b/table.go
index de4807af..26c31e0e 100644
--- a/table.go
+++ b/table.go
@@ -161,6 +161,16 @@ const (
 	UNIONUNIQUE
 )
 
+type Index struct {
+	Name     string
+	IsUnique bool
+	Cols     []*Column
+}
+
+func NewIndex(name string, isUnique bool) *Index {
+	return &Index{name, isUnique, make([]*Column, 0)}
+}
+
 type Column struct {
 	Name            string
 	FieldName       string
diff --git a/xorm.go b/xorm.go
index c85d8f55..d2dc91eb 100644
--- a/xorm.go
+++ b/xorm.go
@@ -17,16 +17,12 @@ func close(engine *Engine) {
 	engine.Close()
 }
 
-// new a db manager according to the parameter. Currently support three
-// driver
+// new a db manager according to the parameter. Currently support four
+// drivers
 func NewEngine(driverName string, dataSourceName string) (*Engine, error) {
-	engine := &Engine{ShowSQL: false, DriverName: driverName, Mapper: SnakeMapper{},
-		DataSourceName: dataSourceName}
+	engine := &Engine{DriverName: driverName, Mapper: SnakeMapper{},
+		DataSourceName: dataSourceName, Filters: make([]Filter, 0)}
 
-	engine.Tables = make(map[reflect.Type]*Table)
-	engine.mutex = &sync.Mutex{}
-	engine.TagIdentifier = "xorm"
-	engine.Filters = make([]Filter, 0)
 	if driverName == SQLITE {
 		engine.Dialect = &sqlite3{}
 	} else if driverName == MYSQL {
@@ -34,19 +30,28 @@ func NewEngine(driverName string, dataSourceName string) (*Engine, error) {
 	} else if driverName == POSTGRES {
 		engine.Dialect = &postgres{}
 		engine.Filters = append(engine.Filters, &PgSeqFilter{})
-		engine.Filters = append(engine.Filters, &PgQuoteFilter{})
+		engine.Filters = append(engine.Filters, &QuoteFilter{})
 	} else if driverName == MYMYSQL {
-		engine.Dialect = &mysql{}
+		engine.Dialect = &mymysql{}
 	} else {
 		return nil, errors.New(fmt.Sprintf("Unsupported driver name: %v", driverName))
 	}
+	err := engine.Dialect.Init(dataSourceName)
+	if err != nil {
+		return nil, err
+	}
+
+	engine.Tables = make(map[reflect.Type]*Table)
+	engine.mutex = &sync.Mutex{}
+	engine.TagIdentifier = "xorm"
+
 	engine.Filters = append(engine.Filters, &IdFilter{})
 	engine.Logger = os.Stdout
 
 	//engine.Pool = NewSimpleConnectPool()
 	//engine.Pool = NewNoneConnectPool()
 	//engine.Cacher = NewLRUCacher()
-	err := engine.SetPool(NewSysConnectPool())
+	err = engine.SetPool(NewSysConnectPool())
 	runtime.SetFinalizer(engine, close)
 	return engine, err
 }