diff --git a/lib/adapters/mysql.js b/lib/adapters/mysql.js
index bf0e9ce..c84be4b 100644
--- a/lib/adapters/mysql.js
+++ b/lib/adapters/mysql.js
@@ -568,7 +568,7 @@ class MySQLAdapter extends Adapter {
                 sql += ` ${index}`;
             }
         }
-        
+
         sql += ` SET ${set}`;
 
         if(options.where && Object.keys(options.where).length) {
@@ -680,7 +680,7 @@ class MySQLAdapter extends Adapter {
         this.execute(options.conn, sql, function(err, rows) {
             if(err) {
                 return callback(err, undefined, sql);
-            } 
+            }
 
             if(options.single) {
                 return callback(undefined, (rows || []).length ? rows[0] : null, sql);
@@ -983,7 +983,7 @@ class MySQLAdapter extends Adapter {
                 options.fields = primaryKeys;
 
                 let relatedSql;
-               
+
                 try {
                     relatedSql = self.makeSql("find", query.model, options);
                 } catch(e) {
@@ -1018,7 +1018,7 @@ class MySQLAdapter extends Adapter {
      * @param {Object} data data to be inserted
      * @param {Function} callback the callback function
      */
-    insert(model, conn, data, callback) { 
+    insert(model, conn, data, callback) {
         // fill data into sql string
         //
         // INSERT INTO `name` SET =>
@@ -1056,14 +1056,14 @@ class MySQLAdapter extends Adapter {
             // query the instance from database now
             if(row.insertId) {
                 // if this row has an auto increament id
-               
+
                 if(primaryKeys.length === 1) {
                     // if we have only one primary key
                     //
                     // 1. no AI specified in model: consume primary is AI in database, use AI as primary key to query
                     // 2. primary key is AI: use AI as primary key to query
                     // 3. primary key is not AI: use primary key to query
-                    
+
                     if(!autoIncrement || autoIncrement.primaryKey) {
                         where[primaryKeys[0].name] = row.insertId;
                     } else {
@@ -1077,7 +1077,7 @@ class MySQLAdapter extends Adapter {
                     //
                     // step 2. (only have auto increament key)
                     //   overwrite the AI to the certain primary key
-                   
+
                     // --> step 1.
                     where = primaryValues;
 
@@ -1104,7 +1104,12 @@ class MySQLAdapter extends Adapter {
                 where = primaryValues;
             }
 
-            model.where(where).findOne(function(err, row) {
+            let _model = model;
+            if(conn) {
+                _model = _model.conn(conn);
+            }
+
+            _model.where(where).findOne(function(err, row) {
                 if(err) {
                     return callback(err, undefined, sql);
                 }