diff --git a/engine.go b/engine.go
index cfa0933e..654051f1 100644
--- a/engine.go
+++ b/engine.go
@@ -273,21 +273,6 @@ func (engine *Engine) logSQL(sqlStr string, sqlArgs ...interface{}) {
 	}
 }
 
-func (engine *Engine) logSQLQueryTime(sqlStr string, args []interface{}, executionBlock func() (*core.Stmt, *core.Rows, error)) (*core.Stmt, *core.Rows, error) {
-	if engine.showSQL && engine.showExecTime {
-		b4ExecTime := time.Now()
-		stmt, res, err := executionBlock()
-		execDuration := time.Since(b4ExecTime)
-		if len(args) > 0 {
-			engine.logger.Infof("[SQL] %s %v - took: %v", sqlStr, args, execDuration)
-		} else {
-			engine.logger.Infof("[SQL] %s - took: %v", sqlStr, execDuration)
-		}
-		return stmt, res, err
-	}
-	return executionBlock()
-}
-
 func (engine *Engine) logSQLExecutionTime(sqlStr string, args []interface{}, executionBlock func() (sql.Result, error)) (sql.Result, error) {
 	if engine.showSQL && engine.showExecTime {
 		b4ExecTime := time.Now()
diff --git a/rows.go b/rows.go
index 444e3d43..258d9f27 100644
--- a/rows.go
+++ b/rows.go
@@ -17,7 +17,6 @@ type Rows struct {
 	NoTypeCheck bool
 
 	session   *Session
-	stmt      *core.Stmt
 	rows      *core.Rows
 	fields    []string
 	beanType  reflect.Type
@@ -29,8 +28,6 @@ func newRows(session *Session, bean interface{}) (*Rows, error) {
 	rows.session = session
 	rows.beanType = reflect.Indirect(reflect.ValueOf(bean)).Type()
 
-	defer rows.session.resetStatement()
-
 	var sqlStr string
 	var args []interface{}
 	var err error
@@ -53,32 +50,11 @@ func newRows(session *Session, bean interface{}) (*Rows, error) {
 		args = rows.session.statement.RawParams
 	}
 
-	for _, filter := range rows.session.engine.dialect.Filters() {
-		sqlStr = filter.Do(sqlStr, session.engine.dialect, rows.session.statement.RefTable)
-	}
-
-	rows.session.saveLastSQL(sqlStr, args...)
-	if rows.session.prepareStmt {
-		rows.stmt, err = rows.session.DB().Prepare(sqlStr)
-		if err != nil {
-			rows.lastError = err
-			rows.Close()
-			return nil, err
-		}
-
-		rows.rows, err = rows.stmt.Query(args...)
-		if err != nil {
-			rows.lastError = err
-			rows.Close()
-			return nil, err
-		}
-	} else {
-		rows.rows, err = rows.session.DB().Query(sqlStr, args...)
-		if err != nil {
-			rows.lastError = err
-			rows.Close()
-			return nil, err
-		}
+	rows.rows, err = rows.session.queryRows(sqlStr, args...)
+	if err != nil {
+		rows.lastError = err
+		rows.Close()
+		return nil, err
 	}
 
 	rows.fields, err = rows.rows.Columns()
@@ -142,17 +118,10 @@ func (rows *Rows) Close() error {
 		if rows.rows != nil {
 			rows.lastError = rows.rows.Close()
 			if rows.lastError != nil {
-				defer rows.stmt.Close()
 				return rows.lastError
 			}
 		}
-		if rows.stmt != nil {
-			rows.lastError = rows.stmt.Close()
-		}
 	} else {
-		if rows.stmt != nil {
-			defer rows.stmt.Close()
-		}
 		if rows.rows != nil {
 			defer rows.rows.Close()
 		}
diff --git a/session.go b/session.go
index 9d041402..6f7aca32 100644
--- a/session.go
+++ b/session.go
@@ -777,14 +777,6 @@ func (session *Session) slice2Bean(scanResults []interface{}, fields []string, f
 	return pk, nil
 }
 
-func (session *Session) queryPreprocess(sqlStr *string, paramStr ...interface{}) {
-	for _, filter := range session.engine.dialect.Filters() {
-		*sqlStr = filter.Do(*sqlStr, session.engine.dialect, session.statement.RefTable)
-	}
-
-	session.saveLastSQL(*sqlStr, paramStr...)
-}
-
 // saveLastSQL stores executed query information
 func (session *Session) saveLastSQL(sql string, args ...interface{}) {
 	session.lastSQL = sql
diff --git a/session_delete.go b/session_delete.go
index 9fd7b8af..324cfba3 100644
--- a/session_delete.go
+++ b/session_delete.go
@@ -31,7 +31,7 @@ func (session *Session) cacheDelete(sqlStr string, args ...interface{}) error {
 	tableName := session.statement.TableName()
 	ids, err := core.GetCacheSql(cacher, tableName, newsql, args)
 	if err != nil {
-		resultsSlice, err := session.query(newsql, args...)
+		resultsSlice, err := session.queryBytes(newsql, args...)
 		if err != nil {
 			return err
 		}
diff --git a/session_exist.go b/session_exist.go
index 91d1cd60..e24ee121 100644
--- a/session_exist.go
+++ b/session_exist.go
@@ -10,7 +10,6 @@ import (
 	"reflect"
 
 	"github.com/go-xorm/builder"
-	"github.com/go-xorm/core"
 )
 
 // Exist returns true if the record exist otherwise return false
@@ -69,19 +68,11 @@ func (session *Session) Exist(bean ...interface{}) (bool, error) {
 		args = session.statement.RawParams
 	}
 
-	session.queryPreprocess(&sqlStr, args...)
-
-	var rawRows *core.Rows
-	if session.isAutoCommit {
-		_, rawRows, err = session.innerQuery(sqlStr, args...)
-	} else {
-		rawRows, err = session.tx.Query(sqlStr, args...)
-	}
+	rows, err := session.queryRows(sqlStr, args...)
 	if err != nil {
 		return false, err
 	}
+	defer rows.Close()
 
-	defer rawRows.Close()
-
-	return rawRows.Next(), nil
+	return rows.Next(), nil
 }
diff --git a/session_find.go b/session_find.go
index 42b3506e..8115928d 100644
--- a/session_find.go
+++ b/session_find.go
@@ -157,21 +157,13 @@ func (session *Session) Find(rowsSlicePtr interface{}, condiBean ...interface{})
 }
 
 func (session *Session) noCacheFind(table *core.Table, containerValue reflect.Value, sqlStr string, args ...interface{}) error {
-	var rawRows *core.Rows
-	var err error
-
-	session.queryPreprocess(&sqlStr, args...)
-	if session.isAutoCommit {
-		_, rawRows, err = session.innerQuery(sqlStr, args...)
-	} else {
-		rawRows, err = session.tx.Query(sqlStr, args...)
-	}
+	rows, err := session.queryRows(sqlStr, args...)
 	if err != nil {
 		return err
 	}
-	defer rawRows.Close()
+	defer rows.Close()
 
-	fields, err := rawRows.Columns()
+	fields, err := rows.Columns()
 	if err != nil {
 		return err
 	}
@@ -245,20 +237,20 @@ func (session *Session) noCacheFind(table *core.Table, containerValue reflect.Va
 		if err != nil {
 			return err
 		}
-		return session.rows2Beans(rawRows, fields, len(fields), tb, newElemFunc, containerValueSetFunc)
+		return session.rows2Beans(rows, fields, len(fields), tb, newElemFunc, containerValueSetFunc)
 	}
 
-	for rawRows.Next() {
+	for rows.Next() {
 		var newValue = newElemFunc(fields)
 		bean := newValue.Interface()
 
 		switch elemType.Kind() {
 		case reflect.Slice:
-			err = rawRows.ScanSlice(bean)
+			err = rows.ScanSlice(bean)
 		case reflect.Map:
-			err = rawRows.ScanMap(bean)
+			err = rows.ScanMap(bean)
 		default:
-			err = rawRows.Scan(bean)
+			err = rows.Scan(bean)
 		}
 
 		if err != nil {
diff --git a/session_get.go b/session_get.go
index d5f768c6..e5c67d4b 100644
--- a/session_get.go
+++ b/session_get.go
@@ -65,30 +65,21 @@ func (session *Session) Get(bean interface{}) (bool, error) {
 }
 
 func (session *Session) nocacheGet(beanKind reflect.Kind, bean interface{}, sqlStr string, args ...interface{}) (bool, error) {
-	session.queryPreprocess(&sqlStr, args...)
-
-	var rawRows *core.Rows
-	var err error
-	if session.isAutoCommit {
-		_, rawRows, err = session.innerQuery(sqlStr, args...)
-	} else {
-		rawRows, err = session.tx.Query(sqlStr, args...)
-	}
+	rows, err := session.queryRows(sqlStr, args...)
 	if err != nil {
 		return false, err
 	}
+	defer rows.Close()
 
-	defer rawRows.Close()
-
-	if !rawRows.Next() {
+	if !rows.Next() {
 		return false, nil
 	}
 
 	switch beanKind {
 	case reflect.Struct:
-		fields, err := rawRows.Columns()
+		fields, err := rows.Columns()
 		if err != nil {
-			// WARN: Alougth rawRows return true, but get fields failed
+			// WARN: Alougth rows return true, but get fields failed
 			return true, err
 		}
 		dataStruct := rValue(bean)
@@ -96,19 +87,20 @@ func (session *Session) nocacheGet(beanKind reflect.Kind, bean interface{}, sqlS
 			return false, err
 		}
 
-		scanResults, err := session.row2Slice(rawRows, fields, len(fields), bean)
+		scanResults, err := session.row2Slice(rows, fields, len(fields), bean)
 		if err != nil {
 			return false, err
 		}
-		rawRows.Close()
+		// close it before covert data
+		rows.Close()
 
 		_, err = session.slice2Bean(scanResults, fields, len(fields), bean, &dataStruct, session.statement.RefTable)
 	case reflect.Slice:
-		err = rawRows.ScanSlice(bean)
+		err = rows.ScanSlice(bean)
 	case reflect.Map:
-		err = rawRows.ScanMap(bean)
+		err = rows.ScanMap(bean)
 	default:
-		err = rawRows.Scan(bean)
+		err = rows.Scan(bean)
 	}
 
 	return true, err
diff --git a/session_insert.go b/session_insert.go
index 02edf574..350242bc 100644
--- a/session_insert.go
+++ b/session_insert.go
@@ -395,7 +395,7 @@ func (session *Session) innerInsert(bean interface{}) (int64, error) {
 	// for postgres, many of them didn't implement lastInsertId, so we should
 	// implemented it ourself.
 	if session.engine.dialect.DBType() == core.ORACLE && len(table.AutoIncrement) > 0 {
-		res, err := session.query("select seq_atable.currval from dual", args...)
+		res, err := session.queryBytes("select seq_atable.currval from dual", args...)
 		if err != nil {
 			return 0, err
 		}
@@ -440,7 +440,7 @@ func (session *Session) innerInsert(bean interface{}) (int64, error) {
 	} else if session.engine.dialect.DBType() == core.POSTGRES && len(table.AutoIncrement) > 0 {
 		//assert table.AutoIncrement != ""
 		sqlStr = sqlStr + " RETURNING " + session.engine.Quote(table.AutoIncrement)
-		res, err := session.query(sqlStr, args...)
+		res, err := session.queryBytes(sqlStr, args...)
 
 		if err != nil {
 			return 0, err
diff --git a/session_raw.go b/session_raw.go
index 6225fed2..67f042fd 100644
--- a/session_raw.go
+++ b/session_raw.go
@@ -14,55 +14,6 @@ import (
 	"github.com/go-xorm/core"
 )
 
-func (session *Session) query(sqlStr string, paramStr ...interface{}) ([]map[string][]byte, error) {
-	session.queryPreprocess(&sqlStr, paramStr...)
-
-	if session.isAutoCommit {
-		return session.innerQuery2(sqlStr, paramStr...)
-	}
-	return session.txQuery(session.tx, sqlStr, paramStr...)
-}
-
-func (session *Session) txQuery(tx *core.Tx, sqlStr string, params ...interface{}) ([]map[string][]byte, error) {
-	rows, err := tx.Query(sqlStr, params...)
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-
-	return rows2maps(rows)
-}
-
-func (session *Session) innerQuery(sqlStr string, params ...interface{}) (*core.Stmt, *core.Rows, error) {
-	var callback func() (*core.Stmt, *core.Rows, error)
-	if session.prepareStmt {
-		callback = func() (*core.Stmt, *core.Rows, error) {
-			stmt, err := session.doPrepare(sqlStr)
-			if err != nil {
-				return nil, nil, err
-			}
-			rows, err := stmt.Query(params...)
-			if err != nil {
-				return nil, nil, err
-			}
-			return stmt, rows, nil
-		}
-	} else {
-		callback = func() (*core.Stmt, *core.Rows, error) {
-			rows, err := session.DB().Query(sqlStr, params...)
-			if err != nil {
-				return nil, nil, err
-			}
-			return nil, rows, err
-		}
-	}
-	stmt, rows, err := session.engine.logSQLQueryTime(sqlStr, params, callback)
-	if err != nil {
-		return nil, nil, err
-	}
-	return stmt, rows, nil
-}
-
 func rows2maps(rows *core.Rows) (resultsSlice []map[string][]byte, err error) {
 	fields, err := rows.Columns()
 	if err != nil {
@@ -117,27 +68,6 @@ func row2map(rows *core.Rows, fields []string) (resultsMap map[string][]byte, er
 	return result, nil
 }
 
-func (session *Session) innerQuery2(sqlStr string, params ...interface{}) ([]map[string][]byte, error) {
-	_, rows, err := session.innerQuery(sqlStr, params...)
-	if rows != nil {
-		defer rows.Close()
-	}
-	if err != nil {
-		return nil, err
-	}
-	return rows2maps(rows)
-}
-
-// Query runs a raw sql and return records as []map[string][]byte
-func (session *Session) Query(sqlStr string, paramStr ...interface{}) ([]map[string][]byte, error) {
-	defer session.resetStatement()
-	if session.isAutoClose {
-		defer session.Close()
-	}
-
-	return session.query(sqlStr, paramStr...)
-}
-
 func rows2Strings(rows *core.Rows) (resultsSlice []map[string]string, err error) {
 	fields, err := rows.Columns()
 	if err != nil {
@@ -234,42 +164,136 @@ func row2mapStr(rows *core.Rows, fields []string) (resultsMap map[string]string,
 	return result, nil
 }
 
-func txQuery2(tx *core.Tx, sqlStr string, params ...interface{}) ([]map[string]string, error) {
-	rows, err := tx.Query(sqlStr, params...)
-	if err != nil {
-		return nil, err
+func (session *Session) queryPreprocess(sqlStr *string, paramStr ...interface{}) {
+	for _, filter := range session.engine.dialect.Filters() {
+		*sqlStr = filter.Do(*sqlStr, session.engine.dialect, session.statement.RefTable)
 	}
-	defer rows.Close()
 
-	return rows2Strings(rows)
+	session.lastSQL = *sqlStr
+	session.lastSQLArgs = paramStr
 }
 
-func query2(db *core.DB, sqlStr string, params ...interface{}) ([]map[string]string, error) {
-	rows, err := db.Query(sqlStr, params...)
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-	return rows2Strings(rows)
-}
-
-// QueryString runs a raw sql and return records as []map[string]string
-func (session *Session) QueryString(sqlStr string, args ...interface{}) ([]map[string]string, error) {
+func (session *Session) queryRows(sqlStr string, args ...interface{}) (*core.Rows, error) {
 	defer session.resetStatement()
+
+	session.queryPreprocess(&sqlStr, args...)
+
+	if session.engine.showSQL {
+		if session.engine.showExecTime {
+			b4ExecTime := time.Now()
+			defer func() {
+				execDuration := time.Since(b4ExecTime)
+				if len(args) > 0 {
+					session.engine.logger.Infof("[SQL] %s %#v - took: %v", sqlStr, args, execDuration)
+				} else {
+					session.engine.logger.Infof("[SQL] %s - took: %v", sqlStr, execDuration)
+				}
+			}()
+		} else {
+			if len(args) > 0 {
+				session.engine.logger.Infof("[SQL] %v %#v", sqlStr, args)
+			} else {
+				session.engine.logger.Infof("[SQL] %v", sqlStr)
+			}
+		}
+	}
+
+	if session.isAutoCommit {
+		if session.prepareStmt {
+			// don't clear stmt since session will cache them
+			stmt, err := session.doPrepare(sqlStr)
+			if err != nil {
+				return nil, err
+			}
+
+			rows, err := stmt.Query(args...)
+			if err != nil {
+				return nil, err
+			}
+			return rows, nil
+		}
+
+		rows, err := session.DB().Query(sqlStr, args...)
+		if err != nil {
+			return nil, err
+		}
+		return rows, nil
+	}
+
+	rows, err := session.tx.Query(sqlStr, args...)
+	if err != nil {
+		return nil, err
+	}
+	return rows, nil
+}
+
+func (session *Session) queryRow(sqlStr string, args ...interface{}) *core.Row {
+	return core.NewRow(session.queryRows(sqlStr, args...))
+}
+
+func (session *Session) queryBytes(sqlStr string, args ...interface{}) ([]map[string][]byte, error) {
+	rows, err := session.queryRows(sqlStr, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	return rows2maps(rows)
+}
+
+// Query runs a raw sql and return records as []map[string][]byte
+func (session *Session) Query(sqlStr string, args ...interface{}) ([]map[string][]byte, error) {
 	if session.isAutoClose {
 		defer session.Close()
 	}
 
-	session.queryPreprocess(&sqlStr, args...)
-
-	if session.isAutoCommit {
-		return query2(session.DB(), sqlStr, args...)
-	}
-	return txQuery2(session.tx, sqlStr, args...)
+	return session.queryBytes(sqlStr, args...)
 }
 
-// Execute sql
-func (session *Session) innerExec(sqlStr string, args ...interface{}) (sql.Result, error) {
+// QueryString runs a raw sql and return records as []map[string]string
+func (session *Session) QueryString(sqlStr string, args ...interface{}) ([]map[string]string, error) {
+	if session.isAutoClose {
+		defer session.Close()
+	}
+
+	rows, err := session.queryRows(sqlStr, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	return rows2Strings(rows)
+}
+
+func (session *Session) exec(sqlStr string, args ...interface{}) (sql.Result, error) {
+	defer session.resetStatement()
+
+	session.queryPreprocess(&sqlStr, args...)
+
+	if session.engine.showSQL {
+		if session.engine.showExecTime {
+			b4ExecTime := time.Now()
+			defer func() {
+				execDuration := time.Since(b4ExecTime)
+				if len(args) > 0 {
+					session.engine.logger.Infof("[SQL] %s %#v - took: %v", sqlStr, args, execDuration)
+				} else {
+					session.engine.logger.Infof("[SQL] %s - took: %v", sqlStr, execDuration)
+				}
+			}()
+		} else {
+			if len(args) > 0 {
+				session.engine.logger.Infof("[SQL] %v %#v", sqlStr, args)
+			} else {
+				session.engine.logger.Infof("[SQL] %v", sqlStr)
+			}
+		}
+	}
+
+	if !session.isAutoCommit {
+		return session.tx.Exec(sqlStr, args...)
+	}
+
 	if session.prepareStmt {
 		stmt, err := session.doPrepare(sqlStr)
 		if err != nil {
@@ -286,32 +310,8 @@ func (session *Session) innerExec(sqlStr string, args ...interface{}) (sql.Resul
 	return session.DB().Exec(sqlStr, args...)
 }
 
-func (session *Session) exec(sqlStr string, args ...interface{}) (sql.Result, error) {
-	for _, filter := range session.engine.dialect.Filters() {
-		// TODO: for table name, it's no need to RefTable
-		sqlStr = filter.Do(sqlStr, session.engine.dialect, session.statement.RefTable)
-	}
-
-	session.saveLastSQL(sqlStr, args...)
-
-	return session.engine.logSQLExecutionTime(sqlStr, args, func() (sql.Result, error) {
-		if session.isAutoCommit {
-			// FIXME: oci8 can not auto commit (github.com/mattn/go-oci8)
-			if session.engine.dialect.DBType() == core.ORACLE {
-				session.Begin()
-				r, err := session.tx.Exec(sqlStr, args...)
-				session.Commit()
-				return r, err
-			}
-			return session.innerExec(sqlStr, args...)
-		}
-		return session.tx.Exec(sqlStr, args...)
-	})
-}
-
 // Exec raw sql
 func (session *Session) Exec(sqlStr string, args ...interface{}) (sql.Result, error) {
-	defer session.resetStatement()
 	if session.isAutoClose {
 		defer session.Close()
 	}
diff --git a/session_schema.go b/session_schema.go
index c1d5088d..9442715a 100644
--- a/session_schema.go
+++ b/session_schema.go
@@ -142,7 +142,7 @@ func (session *Session) dropTable(beanOrTableName interface{}) error {
 	var needDrop = true
 	if !session.engine.dialect.SupportDropIfExists() {
 		sqlStr, args := session.engine.dialect.TableCheckSql(tableName)
-		results, err := session.query(sqlStr, args...)
+		results, err := session.queryBytes(sqlStr, args...)
 		if err != nil {
 			return err
 		}
@@ -174,7 +174,7 @@ func (session *Session) IsTableExist(beanOrTableName interface{}) (bool, error)
 func (session *Session) isTableExist(tableName string) (bool, error) {
 	defer session.resetStatement()
 	sqlStr, args := session.engine.dialect.TableCheckSql(tableName)
-	results, err := session.query(sqlStr, args...)
+	results, err := session.queryBytes(sqlStr, args...)
 	return len(results) > 0, err
 }
 
@@ -200,8 +200,7 @@ func (session *Session) isTableEmpty(tableName string) (bool, error) {
 
 	var total int64
 	sqlStr := fmt.Sprintf("select count(*) from %s", session.engine.Quote(tableName))
-	err := session.DB().QueryRow(sqlStr).Scan(&total)
-	session.saveLastSQL(sqlStr)
+	err := session.queryRow(sqlStr).Scan(&total)
 	if err != nil {
 		if err == sql.ErrNoRows {
 			err = nil
diff --git a/session_stats.go b/session_stats.go
index df02e95a..c2cac830 100644
--- a/session_stats.go
+++ b/session_stats.go
@@ -13,7 +13,6 @@ import (
 // Count counts the records. bean's non-empty fields
 // are conditions.
 func (session *Session) Count(bean ...interface{}) (int64, error) {
-	defer session.resetStatement()
 	if session.isAutoClose {
 		defer session.Close()
 	}
@@ -31,15 +30,8 @@ func (session *Session) Count(bean ...interface{}) (int64, error) {
 		args = session.statement.RawParams
 	}
 
-	session.queryPreprocess(&sqlStr, args...)
-
 	var total int64
-	if session.isAutoCommit {
-		err = session.DB().QueryRow(sqlStr, args...).Scan(&total)
-	} else {
-		err = session.tx.QueryRow(sqlStr, args...).Scan(&total)
-	}
-
+	err = session.queryRow(sqlStr, args...).Scan(&total)
 	if err == sql.ErrNoRows || err == nil {
 		return total, nil
 	}
@@ -49,7 +41,6 @@ func (session *Session) Count(bean ...interface{}) (int64, error) {
 
 // sum call sum some column. bean's non-empty fields are conditions.
 func (session *Session) sum(res interface{}, bean interface{}, columnNames ...string) error {
-	defer session.resetStatement()
 	if session.isAutoClose {
 		defer session.Close()
 	}
@@ -73,22 +64,11 @@ func (session *Session) sum(res interface{}, bean interface{}, columnNames ...st
 		args = session.statement.RawParams
 	}
 
-	session.queryPreprocess(&sqlStr, args...)
-
 	if isSlice {
-		if session.isAutoCommit {
-			err = session.DB().QueryRow(sqlStr, args...).ScanSlice(res)
-		} else {
-			err = session.tx.QueryRow(sqlStr, args...).ScanSlice(res)
-		}
+		err = session.queryRow(sqlStr, args...).ScanSlice(res)
 	} else {
-		if session.isAutoCommit {
-			err = session.DB().QueryRow(sqlStr, args...).Scan(res)
-		} else {
-			err = session.tx.QueryRow(sqlStr, args...).Scan(res)
-		}
+		err = session.queryRow(sqlStr, args...).Scan(res)
 	}
-
 	if err == sql.ErrNoRows || err == nil {
 		return nil
 	}