System.Data.ConstraintException: Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints. at System.Data.DataTable.EnableConstraints() at System.Data.DataTable.set_EnforceConstraints(Boolea…

InnoDB表中中Foreign Key定义 1. InnoDB允许a foreign key引用一个索引列或者索引组列. 2. InnoDB现在并不支持用户定义的分区表有foreign keys,这意味着不包含用户定义的分区表InnoDB可以包含foreign key引用,或者被foreign keys引用的列. 3. InnoDB允许a foreign key constraint引用一个non-unique的key,这是对标准SQL的扩展 Foreign Key引用行为 1. SET DE…

Windows8下使用Cisco Systems VPN Client创建的Cisco IPSec VPN无法连接,提示Reason 442: Failed to Enable Virtual Adapter,这个问题是Windows8特有的,不能用其他系统的解决方案解决此问题.下面给出解决方案. 以下内容翻译自Why Cisco VPN Client fails to enable virtual adapter in Windows 8? This doesn’t allow me to c…

今天在家用VPN软件连接,出现了“vpn 422 failed to enable virtual adapter”的错误,系统安装的是Win8专业版32位,百度了半天又很多方法解决不了,后来发现了一个地方能解决,就是更改注册表的东西. 具体看下面 进入注册表regeditHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\CVirtA找到DisplayName,x86系统的将值"@oem16.inf,%CVirtA_Desc%;Cisco…

大公司里肯定涉及不同地点的办公问题,这样VPN的使用就频繁了,今天遇到一个VPN连接问题,分享给大家,看一眼,以后不在这问题上耗费太多功夫. 在win7上连接vpn时抛出“failed to enable virtual adapter.Connection terminated on: +日期”的error,参考百度提出的解决方案,现在mark一下.  “开始” – “运行” – “services.msc” – 停止 “Internet Connection Sharing (ICS)” 只…

Cisco VPN on Windows 8.1 – Reason 442: Failed to enable Virtual Adapter https://supertekboy.com/2013/10/19/cisco-vpn-on-windows-8-1-reason-442-failed-to-enable-virtual-adapter/#.VcWmjs_vPIV   Secure VPN Connection terminated locally by the Client.Rea…

failed to open stream: operation failed 错误详细信息: [Composer\Downloader\TransportException] The "https://packagist.laravel-china.org/packages.json" file could not be downloaded: Peer certificate CN=`*.phphub.org' did not match expected CN=`packagis…

oreign key constraints (also known as referential constraints or referential integrity constraints) enable you to define required relationships between and within tables. For example, a typical foreign key constraint might state that every employee i…

<Windows Azure Platform 系列文章目录> 在Azure Cosmos DB中,还支持Unique Key Constraints(唯一键约束). 我们可以在Azure CosmosDB的一个或者多个字段(Field),建立Unique Key Constraints 通过使用Cosmos DB Unique Key(唯一键约束),可以保证数据是唯一的,避免出现重复的数据. 举个例子,假设我们使用Azure Comos DB,创建员工管理系统(CRM, Customer R…

sqlite外键约束中.restrict约束:如果要删除父表,则子表需空. 如果没有定义约束.会报错,需设置一个约束.…