Question

c＃代码不起作用：

string connectionString = "Provider=OvHOleDbProv.OvHOleDbProv.1;Persist Security Info=True;User ID=user;Password=password;Data Source=192.168.7.96;Location=\"\";Mode=ReadWrite;Extended Properties=\"\";";
OleDbConnection _connection = new OleDbConnection(connectionString);
_connection.Open();
DataTable schema = _connection.GetSchema("Tables"); // Exception see below
_connection.Close();

例外：

System.Data.OleDb.OleDbException（0x80004002）：Сбой   “OvHOleDbProv.OvHOleDbProv.1”безсообщенияобошибке，кодрезультата：   E_NOINTERFACE（0x80004002）。

в   System.Data.OleDb.OleDbConnectionInternal.ProcessResults（OleDbHResult   小时）

вSystem.Data.OleDb.OleDbConnectionInternal.GetSchemaRowset（Guid   schema，Object []限制）

вSystem.Data.OleDb.OleDbConnection.GetOleDbSchemaTable（Guid架构，   对象[]限制）

вSystem.Data.OleDb.OleDbMetaDataFactory.PrepareCollection（String   collectionName，String [] restriction，DbConnection connection）

вSystem.Data.ProviderBase.DbMetaDataFactory.GetSchema（DbConnection）   connection，String collectionName，String [] restrictions）

в   System.Data.ProviderBase.DbConnectionInternal.GetSchema（DbConnectionFactory   factory，DbConnectionPoolGroup poolGroup，DbConnection   outerConnection，String collectionName，String [] restriction）

вSystem.Data.OleDb.OleDbConnection.GetSchema（String collectionName，   String [] restrictionValues）

вSystem.Data.OleDb.OleDbConnection.GetSchema（String collectionName）

SourceModule.Ovation.ApiOvation.ExportSignals（String filename）в   E：\ TFS \ VM-TFS \ SAN \来源   代码\ SourceModules \的Ovation \开发\版本   2 \ SourceModule.Ovation \ ApiOvation.cs：строка58

SourceModule.Ovation.Program.Main（String [] args）в   E：\ TFS \ VM-TFS \ SAN \来源   代码\ SourceModules \的Ovation \开发\版本   2 \ SourceModule.Ovation \ Program.cs：строка20

有效的c＃代码：

string connectionString = "Provider=OvHOleDbProv.OvHOleDbProv.1;Persist Security Info=True;User ID=user;Password=password;Data Source=192.168.7.96;Location=\"\";Mode=ReadWrite;Extended Properties=\"\";";
OleDbConnection _connection = new OleDbConnection(connectionString);
_connection.Open();
DataTable schema = _connection.GetSchema("Restrictions");
_connection.Close();

适用于这两种情况的PS代码：

$connectionString='Provider=OvHOleDbProv.OvHOleDbProv.1;Persist Security Info=True;User ID=user;Password=password;Data Source=192.168.7.96;Location="";Mode=ReadWrite;Extended Properties="";' 
$oCon = New-Object System.Data.OleDb.OleDbConnection $connectionString 
$oCon.Open() 
$schema = New-Object System.Data.DataTable
$schema = $oCon.GetSchema("Tables") 
$schema
$schema = $oCon.GetSchema("Restrictions")
$schema
$oCon.Close()

限制输出包括collectionName“Tables”：

CollectionName RestrictionName RestrictionDefault RestrictionNumber
  -------------- --------------- ------------------ --- --------------
  列TABLE_CATALOG 1
  列TABLE_SCHEMA 2
  列TABLE_NAME 3
  列COLUMN_NAME 4
  表TABLE_CATALOG 1
  表TABLE_SCHEMA 2
  表TABLE_NAME 3
  表TABLE_TYPE 4

Answer 1

以下代码返回数据库中的表列表并保存到xml：

string connectionString = "Provider=OvHOleDbProv.OvHOleDbProv.1;Persist Security Info=True;User ID=user;Password=password;Data Source=192.168.7.96;Location=\"\";Mode=ReadWrite;Extended Properties=\"\";";
OleDbConnection connection = new OleDbConnection(connectionString);
connection.Open();
OleDbCommand command = new OleDbCommand() { Connection = connection, CommandText = "select TABLE_NAME from SYSTABLES where TABLE_TYPE='TABLE'" };
OleDbDataReader datareader = command.ExecuteReader();
DataTable data = new DataTable();
data.Load(datareader);
data.TableName = "SYSTABLES"; // necessary for writing to xml
data.WriteXml("tables.xml");
connection.Close();

OleDb数据提供程序给出错误E_NOINTERFACE

1 个答案: