Oracle.dataaccess [FULL • 2026]

This document covers its purpose, architecture, core components, code examples, best practices, and common troubleshooting tips.

Oracle.DataAccess is a mature, powerful, and high-performance driver that has served the .NET community well for decades. However, its reliance on unmanaged DLLs makes deployment cumbersome.

// Create a new Oracle connection using (OracleConnection connection = new OracleConnection(connectionString))

.NET App → Oracle.DataAccess.dll → Oracle Client → SQL*Net → Oracle Database oracle.dataaccess

bulkCopy.DestinationTableName = "TEMP_EMPLOYEES"; bulkCopy.BatchSize = 500; bulkCopy.WriteToServer(dt);

The application directly references Oracle.DataAccess.dll . This assembly exposes standard ADO.NET classes like OracleConnection , OracleCommand , and OracleDataReader .

using (OracleConnection conn = new OracleConnection(connStr)) // Create a new Oracle connection using (OracleConnection

tx.Rollback(); throw;

conn.Open(); using (OracleBulkCopy bulkCopy = new OracleBulkCopy(conn))

using System; using System.Data; using Oracle.ManagedDataAccess.Client; bulkCopy.BatchSize = 500

Console.WriteLine("Exception occurred: " + ex.Message);

The most critical thing to understand about Oracle.DataAccess is that it is .