EF to MySql一般都是用using最后Commit,一直以为最后没Commit,当using调用Dispose会自动Rollback,没想到这儿有个坑,mysql有个bug并不会Rollback,事务也不会关闭,所以再次BeginTransaction就会报An error occurred while starting a transaction on the provider connection. See the inner exception for details.错误详情是Nested transactions are not supported.
所以用 EF to MySql一定要记得try catch Rollback
例子如下
using (var db = new OtoRCEntities()) { using (var tran = db.Database.BeginTransaction()) { try { db.Database.ExecuteSqlCommand("update xxx"); tran.Commit(); } catch (Exception)//这儿try catch 是用来报错了没有Commit,按理说using后应该自动Rollback { } } } using (var db = new OtoRCEntities()) { using (var tran = db.Database.BeginTransaction())//到这儿就会报错 { try { db.Database.ExecuteSqlCommand("update xxx"); tran.Commit(); } catch (Exception) { } } }
具体MySql bug地址: http://bugs.mysql.com/bug.php?id=71502