Welcome
Client APIs and tools
You can use the HCL Informix® implementation of client APIs to develop applications for Informix database servers.
ESQL/C Guide
The HCL® Informix® Enterprise Replication Guide explains how to use , the Informix implementation of Embedded Structured Query Language (SQL) for C (ESQL/C), to create client applications with database-management capabilities.
Dynamic SQL
Determine SQL statements
If you do not know until run time what SQL statement to execute, you can dynamically determine that statement with the DESCRIBE statement and use a dynamic-management structure to hold any values that the statement sends to or receives from the database server.
Dynamic-management structure
If you do not know the number or data types of values sent to or received from the database server, use a dynamic-management structure. A dynamic-management structure allows you to pass a variable-length list of data to the database server, or receive a variable-length list of data from it.
An sqlda structure
The sqlda structure is a C structure (defined in the sqlda.h header file) that holds data returned from a prepared statement.
Descriptive information

HCL Informix® V15.0.0 documentation
Welcome to the documentation for HCL Informix® 15.0.0 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 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 15.0.0 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
  The HCL® Informix® Change Data Capture API Programmer's Guide describes how to program applications to process changed data from HCL Informix databases using the HCL Informix Change Data Capture API.
- Embedded SQLJ for HCL Informix®
  The HCL® Informix® Embedded SQLJ User's Guide contains information about using IBM Informix Embedded SQLJ.
- ESQL/C Guide
  The HCL® Informix® Enterprise Replication Guide explains how to use , the Informix implementation of Embedded Structured Query Language (SQL) for C (ESQL/C), to create client applications with database-management capabilities.
  - What is Informix® ESQL/C?
  - Database server communication
  - Dynamic SQL
    - Using dynamic SQL
    - Determine SQL statements
      If you do not know until run time what SQL statement to execute, you can dynamically determine that statement with the DESCRIBE statement and use a dynamic-management structure to hold any values that the statement sends to or receives from the database server.
      - Dynamic-management structure
        If you do not know the number or data types of values sent to or received from the database server, use a dynamic-management structure. A dynamic-management structure allows you to pass a variable-length list of data to the database server, or receive a variable-length list of data from it.
        A system-descriptor area
        A system-descriptor area is an area of memory declared by to hold data either returned from or sent by a prepared statement. It is the dynamic-management structure that conforms to the X/Open standards.
        An sqlda structure
        The sqlda structure is a C structure (defined in the sqlda.h header file) that holds data returned from a prepared statement.
        Fixed-length portion
        An sqlvar_struct structure
        Descriptive information
      - The DESCRIBE statement
        The DESCRIBE statement obtains information about database columns or expressions in a prepared statement.
      - Determine statement information at run time
      - A fetch array
        A fetch array enables you to increase the number of rows that a single FETCH statement returns from the fetch buffer to an sqlda structure in your program. A fetch array is especially useful when you fetch simple-large-object (TEXT or BYTE) data.
    - A system-descriptor area
      A system-descriptor area is a dynamic-management structure that can hold data that a prepared statement either returns from or sends to the database server. A system-descriptor area conforms to X/Open standards.
    - An sqlda structure
      An sqlda structure is a dynamic-management structure that can hold data that is either returned from or sent to the database server by a prepared statement. It is a C structure defined in the sqlda.h header file.
  - Appendixes
    This section contains additional reference information.
- GLS User's Guide
  The HCL® Informix® GLS User's Guide describes the Global Language Support (GLS) feature available in HCL Informix products.
- Informix GLS API
  The Informix GLS API Programmer's Guide describes the global language support (GLS) application programming interface (API) available in Informix® ESQL/C and HCL Informix modules.
- Informix® Object Interface for C++ Guide
  The Informix® Object Interface for C++ Programmer's Guide describes how to develop HCL Informix client applications by using the object-oriented C++ programming language.
- Informix® ODBC Driver Guide
  The Informix® ODBC Driver Programmer's Manual serves as a user guide and reference for HCL Informix ODBC Driver, which is the Informix implementation of the Microsoft™ Open Database Connectivity (ODBC) interface, Version 3.0.
- .NET provider options
  The HCL Data Server Provider for .NET IBM® DB2® provider option is the preferred Informix® provider for developing new applications.
- HCL Informix 4GL
  This topic provides a link to the Informix 4GL documentation.
- Informix® JDBC Driver Guide
  The HCL® Informix® JDBC Driver Programmer's Guide describes how to install, load, and use HCL Informix JDBC Driver to connect to the Informix database from within a Java™ application or applet.
- 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
  The HCL Informix OLE DB Provider Programmer's Guide describes the software requirements for using HCL Informix® OLE DB Provider, show how to install and configure the provider for your use, and explain how to use Informix OLE DB Provider to enable client applications, such as ActiveX Data Object (ADO) applications and web pages, to access data on the Informix server.
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 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.

Descriptive information

The following table summarizes the sqlda fields that describe the sqlda structure itself.

Table 1. Descriptive fields in the sqlda structure
Field	Data type	Description
desc_name	char[19]	The name of the descriptor; maximum of 18 characters
desc_occ	short	The size of the sqlda structure
desc_next	struct sqlda *	A pointer to the next sqlda structure