Oracle9i Globalization Support Guide Release 1 (9.0.1) July 2001 Part No. A90236-02 Oracle9i Globalization Support Guide, Release 1 (9.0.1) Part No. A90236-02 Copyright © 1996, 2001 Oracle Corporation. All rights reserved. Primary Author: Paul Lane Contributors: Cathy Baird, Winson Chu, Jessica Fan, Yu Gong, Claire Ho, Simon Law, Peter Linsley, Den Raphaely, Shige Takeda, Linus Tanaka, Makoto Tozawa, Barry Trute, Michael Yau, Hiro Yoshioka, Sergiusz Wolicki, Simon Wong Graphic Designer: Valarie Moore The Programs are not intended for use in any nuclear, aviation, mass transit, medical, or other inherently dangerous applications. It shall be the licensee’s responsibility to take all appropriate fail-safe, backup, redundancy and other measures to ensure the safe use of such applications if the Programs are used for such purposes, and Oracle disclaims liability for any damages caused by such use of the Programs. 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Contents Send Us Your Comments .................................................................................................................. xv Preface......................................................................................................................................................... xvii 1 Globalization Support Oracle Server Globalization Support Architecture...................................................................... 1-2 Locale-Independent Operation................................................................................................... 1-2 Multitier Architecture .................................................................................................................. 1-4 Unicode .......................................................................................................................................... 1-5 Globalization Support Features....................................................................................................... 1-5 Language Support ........................................................................................................................ 1-6 Territory Support.......................................................................................................................... 1-6 Date and Time Formats ............................................................................................................... 1-6 Monetary and Numeric Formats................................................................................................ 1-7 Calendars ....................................................................................................................................... 1-7 Linguistic Sorting.......................................................................................................................... 1-7 Character Set Support .................................................................................................................. 1-7 Customization............................................................................................................................... 1-8 2 Choosing a Character Set Character Set Encoding...................................................................................................................... 2-2 What is an Encoded Character Set? ........................................................................................... 2-2 Which Characters to Encode? ..................................................................................................... 2-3 How Many Languages Does a Character Set Support?.......................................................... 2-4 iii How are Characters Encoded?.................................................................................................... 2-8 Oracle's Naming Convention for Character Sets ................................................................... 2-10 Choosing an Oracle Database Character Set ............................................................................... 2-10 Interoperability with System Resources and Applications .................................................. 2-11 Character Set Conversion .......................................................................................................... 2-11 Database Schemas....................................................................................................................... 2-12 Performance Implications.......................................................................................................... 2-12 Restriction .................................................................................................................................... 2-12 Choosing an Oracle NCHAR Character Set............................................................................ 2-13 Restrictions on Character Sets Used to Express Names and Text ....................................... 2-13 Summary of Datatypes and Supported Encoding Schemes................................................. 2-15 Changing the Character Set After Database Creation........................................................... 2-15 Monolingual Database Scenario.................................................................................................... 2-16 Character Set Conversion .......................................................................................................... 2-16 Multilingual Database Scenarios................................................................................................... 2-18 Restricted Multilingual Support............................................................................................... 2-18 Unrestricted Multilingual Support........................................................................................... 2-19 3 Setting Up a Globalization Support Environment Setting NLS Parameters..................................................................................................................... 3-2 Choosing a Locale with the NLS_LANG Initialization Parameter ........................................... 3-4 Specifying NLS_LANG as an Environment Variable.............................................................. 3-6 NLS_LANG Examples ................................................................................................................. 3-6 Overriding Language and Territory Specifications................................................................. 3-6 NLS Database Parameters ........................................................................................................... 3-7 Checking NLS Parameters................................................................................................................. 3-7 NLS Views ..................................................................................................................................... 3-7 OCI Functions................................................................................................................................ 3-8 Language and Territory Parameters................................................................................................. 3-8 Date and Time Parameters .............................................................................................................. 3-14 Date Formats ............................................................................................................................... 3-14 Time Formats..............................................................................................................................