Welcome
Client APIs and tools
You can use the HCL Informix® implementation of client APIs to develop applications for Informix database servers.
GLS User's Guide
These topics describe the Global Language Support (GLS) feature available in HCL® Informix® products.
IBM® Informix® ESQL/C features
These topics explain how the GLS feature affects IBM® Informix® ESQL/C, an SQL application programming interface (API).

HCL Informix® V15.0 documentation
Welcome to the documentation for HCL Informix® 15.0 and related client tools and products.
Product overview
HCL Informix® is a fast and scalable database server that manages traditional relational, object-relational, and dimensional databases. Its small footprint and self-managing capabilities are suited to embedded data-management solutions.
Installing
These topics describe how to install HCL Informix® database servers, client products, and DataBlade® modules.
Administering
In addition to administering the database server, you can tune performance, replicate data, and archive data.
Migrating and upgrading
You can upgrade to the 15.0 release of HCL Informix® or migrate from other database servers to Informix. Upgrading is an in-place migration method that uses your existing hardware and operating system software. Some changes to the Informix database server can affect upgrading from a previous release.
Client APIs and tools
You can use the HCL Informix® implementation of client APIs to develop applications for Informix database servers.
- Change Data Capture API Programmer's Guide
- Embedded SQLJ for HCL Informix®
- ESQL/C Guide
- GLS User's Guide
  These topics describe the Global Language Support (GLS) feature available in HCL® Informix® products.
  - GLS fundamentals
    The Global Language Support (GLS) feature lets HCL® Informix® products handle different languages, cultural conventions, and code sets for Asian, African, European, Latin American, and Middle Eastern countries.
  - GLS environment variables
    HCL Informix® products establish the client, database, and server locales with information from GLS-related environment variables and from data that is stored in the database.
  - SQL features
    These topics explain how the GLS feature affects the HCL® Informix® implementation of SQL.
  - Database server features
    These topics describe how the GLS feature affects the database server.
  - General SQL API features (ESQL/C)
    These topics explain how the GLS feature affects applications that you develop with the HCL Informix® Client Software Development Kit.
  - IBM® Informix® ESQL/C features
    These topics explain how the GLS feature affects IBM® Informix® ESQL/C, an SQL application programming interface (API).
    - Handle non-ASCII characters
      The IBM® Informix® ESQL/C processors obtain the code set for use in Informix ESQL/C source files from the client locale.
    - Define variables for locale-sensitive data
      The SQL data types NCHAR and NVARCHAR support locale-specific data, in the sense that the database server uses localized collation (if the locale defines localized collation), rather than code set order, for sorting data strings of these types.
    - Enhanced ESQL/C library functions
      Informix® SQL API products support locale-specific enhancements to the Informix ESQL/C library functions.
    - Handle code-set conversion
      When the client and database code sets differ, the IBM® Informix® ESQL/C client application performs code-set conversion on character data.
    - The TRIM function
      When you dynamically execute a SELECT statement, the DESCRIBE statement can return information about the columns in the select list of the Projection clause at run time. DESCRIBE returns the data type of a select-list column in the appropriate field of the dynamic-management structure that you use.
  - Appendix
    This section contains additional reference information.
- Informix GLS API
- Informix® Object Interface for C++ Guide
- Informix® ODBC Driver Guide
- Informix .NET Core Provider
  Starting with CSDK 4.50.xC4, Informix .NET Core Provider built with .NET Core SDK/Runtime v3.1 is shipped for Windows x64 and Linux x86_64 platforms.
- Informix® .NET EF Core Provider Guide
- Informix 4GL/SQL
  These topics include information about HCL Informix®4GL and SQL.
- AI and Agent Connectivity
  The Actian MCP (Model Context Protocol) server provides a standardized interface to connect Large Language Model (LLM) agents and AI applications directly to your HCL Informix database.
- Informix® JDBC Driver Guide
- Informix International Language Supplement (ILS) User Guide
  These topics include information about the translated user interface files for Informix® UNIX™ products, locales, and code set conversion tables
- Informix® OLE DB Provider Guide
Embedding Informix®
When you embed HCL Informix®, you can use enterprise-class high-availability and high performance with embeddability features such as easy programmability, a small disk and memory footprint, and silent deployment.
Extending Informix®
Beyond standard relational database objects, HCL Informix® can be extended to handle specialized data types, access methods, routines, and other objects. Informix includes many built-in extensions that are fully integrated in the database server. Informix also provides DataBlade® modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for Informix.
Data warehousing
In addition to designing and implementing Informix® dimensional databases, you can use tools to create data warehouse applications and optimize your data warehouse queries.
Designing databases
The first step in creating a relational database is to construct a data model, which is a precise, complete definition of the data you want to store. After you prepare your data model, you must implement it as a database and tables. To implement your data model, you first select a data type for each column and then you create a database and tables and populate the tables with data. You can also implement fragmentation strategies and control access to your data.
JSON compatibility
You can use the popular JSON-oriented query language created by MongoDB to interact with data stored in HCL Informix®.
Security
You can secure your Informix® database server and the data that is stored in your Informix databases. You can encrypt data, secure connections, control user privileges and access, and audit data security.
SQL programming
You can use the HCL Informix® implementation of the SQL language to develop applications for Informix database servers.
Troubleshooting HCL Informix®
Several troubleshooting techniques, tools, and resources are available for resolving problems that you encounter in your HCL Informix® database server environment.

IBM® Informix® ESQL/C features

These topics explain how the GLS feature affects IBM® Informix® ESQL/C, an SQL application programming interface (API).

These topics also cover GLS information that is specific to Informix® ESQL/C. For additional GLS information for Informix® ESQL/C, see General SQL API features (ESQL/C).

Tip: For features that are not unique to the GLS feature, see the HCL® Informix® Enterprise Replication Guide. For information about the DataBlade® API, a C language API that is provided with HCL Informix®, see the HCL® Informix® DataBlade® API Programmer's Guide.