C# 使用 GetOleDbSchemaTable 检索架构信息(表、列、主键等)

using System.Data;
            using System.Data.OleDb;

OleDbConnection cn = new OleDbConnection();
            DataTable schemaTable;
            //Connect to the Northwind database in SQL Server.
            //Be sure to use an account that has permission to list tables.
            cn.ConnectionString = "Provider=SQLOLEDB;Data Source=server;User ID=sa;
            Password=password;Initial Catalog=Northwind";
            cn.Open();
            //Retrieve schema information about tables.
            //Because tables include tables, views, and other objects,
            //restrict to just TABLE in the Object array of restrictions.
            schemaTable = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables,
            new Object[] {null, null, null, "TABLE"});
            //List the table name from each row in the schema table.
            for (int i = 0; i < schemaTable.Rows.Count; i++) {
            Console.WriteLine(schemaTable.Rows[i].ItemArray[2].ToString());
            }
            //Explicitly close - don‘t wait on garbage collection.
            cn.Close();
            //Pause
            Console.ReadLine();

using System.Data;
            using System.Data.OleDb;

OleDbConnection cn = new OleDbConnection();
            DataTable schemaTable;
            //Connect to the Northwind database in SQL Server.
            //Be sure to use an account that has permission to retrieve table schema.
            cn.ConnectionString = "Provider=SQLOLEDB;Data Source=server;User ID=sa;
            Password=password;Initial Catalog=Northwind";
            cn.Open();
            //Retrieve schema information about the Employees table.
            schemaTable = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables,
            new Object[] {null, null, "Employees", "TABLE"});
            //List the schema info for the Employees table
            //in the format Field Descriptor :Field Value.
            for (int i = 0; i < schemaTable.Columns.Count; i++) {
            Console.WriteLine(schemaTable.Columns[i].ToString() + " : " +
            schemaTable.Rows[0][i].ToString());
            }
            //Explicitly close - don‘t wait on garbage collection.
            cn.Close();
            //Pause
            Console.ReadLine();

using System.Data;
            using System.Data.OleDb;

OleDbConnection cn = new OleDbConnection();
            DataTable schemaTable;
            //Connect to the Northwind database in SQL Server.
            //Be sure to use an account that has permission to list the columns in the Employees table.
            cn.ConnectionString = "Provider=SQLOLEDB;Data Source=server;User ID=sa;
            Password=password;Initial Catalog=Northwind";
            cn.Open();
            //Retrieve schema information about columns.
            //Restrict to just the Employees TABLE.
            schemaTable = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Columns,
            new Object[] {null, null, "Employees", null});
            //List the column name from each row in the schema table.
            for (int i = 0; i < schemaTable.Rows.Count; i++) {
            Console.WriteLine(schemaTable.Rows[i].ItemArray[3].ToString());
            }
            //Explicitly close - don‘t wait on garbage collection.
            cn.Close();
            //Pause
            Console.ReadLine();

using System.Data;
            using System.Data.OleDb;

OleDbConnection cn = new OleDbConnection();
            DataTable schemaTable;
            //Connect to SQL Server.
            //Be sure to use an account that has permissions to list primary keys
            //in both the Northwind and Pubs databases.
            cn.ConnectionString = "Provider=SQLOLEDB;Data Source=server;User ID=sa;
            Password=password;";
            cn.Open();
            //Retrieve schema information about primary keys.
            //Restrict to just the Employees TABLE in the Northwind CATALOG.
            schemaTable = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Primary_Keys,
            new Object[] {"Northwind", "dbo", "Employees"});
            //List the primary key for the first row in the schema table.
            //The first three items in the ItemArray in the row are catalog, schema, and table.
            //The fourth item is the primary key.
            Console.WriteLine(schemaTable.Rows[0].ItemArray[3].ToString());
            //Retrieve primary key for the Employee TABLE in the Pubs CATALOG.
            schemaTable = cn.GetOleDbSchemaTable(OleDbSchemaGuid.Primary_Keys,
            new Object[] {"Pubs", "dbo", "Employee"});
            //List the primary key for the first row in the schema table.
            Console.WriteLine(schemaTable.Rows[0].ItemArray[3].ToString());
            //Explicitly close - don‘t wait on garbage collection.
            cn.Close();
            //Pause
            Console.ReadLine();