GLS Support by IBM Informix Products

GLS support is provided for these IBM Informix products and utilities:

• Informix database servers
• IBM Informix client applications and database server utilities
• The IBM Informix GLS application programming interface

Sections that follow outline the features that GLS support provides for the first two types of IBM Informix products.

For information about how to migrate a database server whose databases contain non-English data, see the IBM Informix: Migration Guide.

Informix Database Servers

GLS was introduced in IBM Informix OnLine Dynamic Server. Previously, ALS language support was provided for non-English databases with Asian (multibyte) characters and NLS language support for non-English databases with single-byte characters. GLS is a single feature that provides support for single-byte and multibyte data in non-English languages. For backward compatibility, GLS products also support all of the NLS environment variables and a subset of the ALS environment variables. For a list of these variables, see the IBM Informix: Migration Guide.

Culture-Specific Features

With the GLS feature, Informix database servers provide support for the following culture-specific features:

• Processing non-ASCII characters and strings

  You can use non-ASCII characters to name user-specifiable database objects, such as tables, columns, views, statements, cursors, and SPL routines, and you can use a collation order that suits local customs.

  You can also use non-ASCII characters in many other contexts. For example, you can use them to specify the WHERE and ORDER BY clauses of your SELECT statements or to sort data in NCHAR and NVARCHAR columns. You can use GLS collation features without the modification of existing code.

• Evaluation of expressions

  You can use non-ASCII characters in expression comparisons that involve NCHAR and NVARCHAR data.

• Translation of locale-specific values for dates, times, numeric data, and monetary data

  You can use end-user formats that are specific to a country or culture outside the U.S. to specify date, time, numeric, and monetary values when they appear in literal strings. The database server can translate these formats to the appropriate internal database format.

• Accessibility of formerly incompatible character code sets

  The client application can perform code-set conversion between convertible code sets to allow you to access and share data between databases and clients that have different code sets. For more information on code-set conversion, see Performing Code-Set Conversion.

IBM Informix Client Applications and Utilities

In general, a client application is a program that runs on a workstation or a PC on a network. To the GLS feature, a client application can be either an IBM Informix SQL API product (such as IBM Informix ESQL/C) or an Informix database server utility (such as DB–Access, dbexport, or onmode). These IBM Informix client applications provide support for the GLS feature:

• The DB–Access utility, which is provided with Informix database servers, allows user-specifiable database objects such as tables, columns, views, statements, cursors, and SPL routines to include non-ASCII characters and to be sorted according to localized collation rules. For more information on identifiers, see Non-ASCII Characters in Identifiers. For general information about DB–Access, refer to the IBM Informix: DB–Access User's Guide.
• The SQL APIs allow host and indicator variable names as well as names of user-specifiable database objects such as tables, columns, views, statements, cursors, and SPL routines to include non-ASCII characters. For more information, see General SQL API Features (ESQL/C).
• Database server utilities such as dbexport or onmode allow many command-line arguments to include non-ASCII characters. For more information, see Database Server Features.
• GLS is also a feature of IBM Informix Dynamic 4GL (Version 3.0 and higher), IBM Informix 4GL (Version 7.2 and higher), and IBM Informix SQL (Version 7.2 and higher). For details of GLS implementation, refer to the documentation of these IBM Informix products.

The IBM Informix GLS Application Programming Interface

IBM Informix GLS is an application programming interface (API) that lets DataBlade module developers and ESQL/C programmers develop internationalized applications with a C-language interface.

The macros and functions of IBM Informix GLS provide access within an application to GLS locales, which contain culture-specific information. You can use IBM Informix GLS to write programs (or change existing programs) to handle different languages, cultural conventions, and code sets.

All IBM Informix GLS functions access the current processing locale, which is the locale that is currently in effect for an application. It is based on either the client locale (for ESQL/C client applications and client LIBMI applications) or the server-processing locale (for DataBlade user-defined routines).

IBM Informix GLS provides macros and functions to help you perform the following internationalization tasks:

• Process single-byte, multibyte, and wide characters
• Process single-byte, multibyte, and wide-character strings
• Memory management for multibyte and wide-character strings
• Convert date, time, money, and number strings to and from binary values
• Process input and output multibyte-character streams

IBM Informix client applications as well as database servers can access IBM Informix GLS. For applications, you link the IBM Informix GLS library to your application to perform locale-related tasks. Informix database servers automatically include the IBM Informix GLS library.

Supported Data Types

The GLS feature supports the following data types:

• SQL character data types
  • CHAR, VARCHAR, NCHAR, and NVARCHAR
  • LVARCHAR
  • TEXT and BYTE

  For information about GLS considerations for the character data types, see Using Character Data Types.

• SQL number and MONEY data types

  For information about GLS considerations for number and MONEY data types, see Numeric and Monetary Formats.

• SQL DATE, and DATETIME data types

  For information about GLS considerations for DATE, and DATETIME data types, see Date and Time Formats.

• User-defined data types
  • Opaque data types
  • Complex data types
  • Distinct data types
• Smart large objects
  • BLOB
  • CLOB

  For GLS considerations regarding user-defined data types and smart large objects, see Handling Extended Data Types (IDS).

• ESQL/C character data types
  • char
  • fixchar
  • string
  • varchar
  • lvarchar

  For information about ESQL/C data types, see the IBM Informix: ESQL/C Programmer's Manual.

Additional GLS Support

IBM Informix products include a core set of GLS locale files, including the default locale and most locales to support English, Western European, Eastern European, Asian, and African territories. If you do not find a locale to support your language and territory, you can get additional locales in the International Language Supplement (ILS) product, which provides all available GLS locales and code-set conversion files. It also includes error messages to support several European languages.

For more information about available GLS locales and IBM Informix Language Supplements, contact your sales representative. For more information about how to create customized message files, see Locating Message Files.