Globalization Support

ODP.NET globalization support enables applications to manipulate culture-sensitive data appropriately. This feature ensures proper string format, date, time, monetary, numeric, sort order, and calendar conventions depending on the Oracle globalization settings.

Note:

  • ODP.NET, Managed Driver and ODP.NET Core are not NLS_LANG sensitive. They are only .NET locale sensitive.

  • ODP.NET, Managed Driver and ODP.NET Core do not support thread-based globalization.

This section includes the following:

Globalization Settings

An OracleGlobalization object can be used to represent the following:

Client Globalization Settings

Client globalization settings are derived from the Oracle globalization setting (NLS_LANG) in the Windows registry of the local computer. The client globalization parameter settings are read-only and remain constant throughout the lifetime of the application. These settings can be obtained by calling the OracleGlobalization.GetClientInfo static method.

The following example retrieves the client globalization settings:

// C#
 
using System;
using Oracle.DataAccess.Client; 
 
class ClientGlobalizationSample
{
  static void Main()
  {
    OracleGlobalization ClientGlob = OracleGlobalization.GetClientInfo();
 
    Console.WriteLine("Client machine language: " + ClientGlob.Language);
    Console.WriteLine("Client characterset: " + ClientGlob.ClientCharacterSet);
  }
}

The properties of the OracleGlobalization object provide the Oracle globalization value settings.

Session Globalization Settings

Session globalization parameters are initially identical to client globalization settings. Unlike client settings, session globalization settings can be updated. However, they can be obtained only after establishing a connection against the database. The session globalization settings can be obtained by calling the GetSessionInfo method on the OracleConnection object. Invoking this method returns an instance of an OracleGlobalization class whose properties represent the globalization settings of the session.

When the OracleConnection object establishes a connection, it implicitly opens a session whose globalization parameters are initialized with those values specified by the client computer's Oracle globalization (or (NLS)) registry settings. The session settings can be updated and can change during its lifetime.

The following example changes the date format setting on the session:

// C#
 
using System;
using Oracle.DataAccess.Client; 
 
class SessionGlobalizationSample
{
  static void Main()
  {
    OracleConnection con = new OracleConnection();
 
    con.ConnectionString = "User Id=scott;Password=tiger;Data Source=oracle;";
    con.Open();
 
    OracleGlobalization SessionGlob = con.GetSessionInfo();
 
    // SetSessionInfo updates the Session with the new value
    SessionGlob.DateFormat = "YYYY/MM/DD";
    con.SetSessionInfo(SessionGlob);
    Console.WriteLine("Date Format successfully changed for the session");
 
    // Close and Dispose OracleConnection object
    con.Close();
    con.Dispose();
  }
}

Thread-Based Globalization Settings

Thread-based globalization parameter settings are specific to each thread. Initially, these settings are identical to the client globalization parameters, but they can be changed as specified by the application. When ODP.NET Types are converted to and from strings, the thread-based globalization parameters are used, if applicable.

Thread-based globalization parameter settings are obtained by invoking the GetThreadInfo static method of the OracleGlobalization class. The SetThreadInfo static method of the OracleGlobalization class can be called to set the thread's globalization settings.

ODP.NET classes and structures rely solely on the OracleGlobalization settings when manipulating culture-sensitive data. They do not use .NET thread culture information. If the application uses only .NET types, OracleGlobalization settings have no effect. However, when conversions are made between ODP.NET types and .NET types, OracleGlobalization settings are used where applicable.

Note:

Changes to the System.Threading.Thread. CurrentThread.CurrentCulture property do not impact the OracleGlobalization settings of the thread or the session, or the reverse.

The following example shows how the thread's globalization settings are used by the ODP.NET Types:

// C#
 
using System;
using Oracle.DataAccess.Types;
using Oracle.DataAccess.Client;
 
class ThreadBasedGlobalizationSample
{
  static void Main(string[] args)
  {
    // Set the thread's DateFormat for the OracleDate constructor
    OracleGlobalization info = OracleGlobalization.GetClientInfo();
    info.DateFormat = "YYYY-MON-DD";
    OracleGlobalization.SetThreadInfo(info);
    
    // construct OracleDate from a string using the DateFormat specified.
    OracleDate date = new OracleDate("1999-DEC-01");
    
    // Set a different DateFormat for the thread
    info.DateFormat = "MM/DD/YYYY";
    OracleGlobalization.SetThreadInfo(info);
 
    // Print "12/01/1999"
    Console.WriteLine(date.ToString()); 
  }
}

The OracleGlobalization object validates property changes made to it. If an invalid value is used to set a property, an exception is thrown. Note that changes made to the Territory and Language properties change other properties of the OracleGlobalization object implicitly.

See Also:

Oracle Database Globalization Support Guide for more information on the properties affected by Territory and Language globalization settings

Globalization-Sensitive Operations

This section lists ODP.NET types and operations that are dependent on or sensitive to globalization settings.

Operations Dependent on Client Computer's Globalization Settings

The OracleString structure depends on the OracleGlobalization settings of the client computer. The client character set of the local computer is used when it converts a Unicode string to a byte[] in the GetNonUnicode method and when it converts a byte[] of ANSI characters to Unicode in the OracleString constructor that accepts a byte[].

Operations Dependent on Thread Globalization Settings

The thread globalization settings are used by ODP.NET types whenever they are converted to and from .NET string types, where applicable. Specific thread globalization settings are used in most cases, depending on the ODP.NET type, by the following:

  • The ToString method

  • The Parse static method

  • Constructors that accept .NET string data

  • Conversion operators to and from .NET strings

For example, the OracleDate type uses the DateFormat property of the thread globalization settings when the ToString method is invoked on it. This returns a DATE as a string in the format specified by the thread's settings.

The thread globalization settings also affect data that is retrieved into the DataSet as a string using Safe Type Mapping. If the type is format-sensitive, the strings are always in the format specified by the thread globalization settings.

For example, INTERVAL DAY TO SECOND data is not affected by thread settings because no format is applicable for this type. However, the DateFormat and NumericCharacters properties can impact the string representation of DATE and NUMBER types, respectively, when they are retrieved as strings into the DataSet through Safe Type Mapping.

See Also:

Operations Sensitive to Session Globalization Parameters

Session globalization settings affect any data that is retrieved from or sent to the database as a string.

For example, if a DATE column is selected with the TO_CHAR function applied on it, the DATE column data will be a string in the date format specified by the DateFormat property of the session globalization settings. Transmitting data in the other direction, the string data that is to be inserted into the DATE column, must be in the format specified by the DateFormat property of the session globalization settings.

ODP.NET Drivers Differences

ODP.NET drivers set the default session time zone differently. While the session time zone for unmanaged ODP.NET uses an hour offset, managed ODP.NET and ODP.NET Core use the region identifier for setting their respective session time zone. As a result, managed and Core ODP.NET is sensitive to daylight savings in scenarios where the timestamp LTZ values have to be converted from or to the session time zone.

There are two methods to resolve this difference if needed. For ODP.NET, Unmanaged Driver, the application explicitly sets the region identifier with the environment variable ORA_SDTZ. For example, set ORA_SDTZ = <Region ID>. If ORA_SDTZ variable is set, Oracle Client considers this value as the session time zone. The second method is to execute an alter session command to set the session time zone property to the region identifier.