Welcome
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.
Creating extensions
You can create user-defined data types, routines, access methods, and other database objects to suit your needs. You can use application programming interfaces to write user-defined routines and applications that access data in Informix® databases.
Function Reference
The IBM® Informix® DataBlade® API Function Reference describes the functions and the subset of functions that the supports.
Categories of functions
This section summarizes by categories the functions that the provides. It divides functions that are valid within modules into several functional categories and lists the functions within each category.
The function library
This section lists the functions in the function library by categories.
Selectivity and cost functions
The provides routines for accessing the MI_FUNCARG data type, which is the data type of all parameters of selectivity and cost functions.

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.
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.
- Informix® extensions and modules
  These topics describe how to use built-in database extensions and separately installed modules.
- Creating extensions
  You can create user-defined data types, routines, access methods, and other database objects to suit your needs. You can use application programming interfaces to write user-defined routines and applications that access data in Informix® databases.
  - Programmer's Guide
    The HCL® Informix® DataBlade® API Programmer's Guide describes information about the , the C-language application programming interface (API) provided with HCL Informix.
  - Function Reference
    The IBM® Informix® DataBlade® API Function Reference describes the functions and the subset of functions that the supports.
    - Categories of functions
      This section summarizes by categories the functions that the provides. It divides functions that are valid within modules into several functional categories and lists the functions within each category.
      - The function library
        This section lists the functions in the function library by categories.
        Data handling
        The provides categories of functions for handling data.
        Session, thread, and transaction management
        The provides categories of functions for managing sessions, threads, and transactions.
        SQL statement processing
        The provides the multiple categories of functions for processing SQL statements.
        User-defined routine execution
        The provides routines for executing user-defined routines (UDRs).
        Selectivity and cost functions
        The provides routines for accessing the MI_FUNCARG data type, which is the data type of all parameters of selectivity and cost functions.
        Memory management
        The provides functions for managing memory.
        Exception handling
        The provides routines for handling exceptions.
        Smart-large-object interface
        The provides routines for handling smart large objects.
        Input and output operations
        The provides functions to perform input and output (I/O) operations.
        Tracing (Server)
        The provides functions for tracing within a user-defined routine.
        Control of the Virtual-Processor environment (Server)
        The provides functions for controlling the Virtual-Processor (VP) environment within a user-defined routine (UDR).
        Database management (Client)
        The provides functions for managing databases in a client LIBMI application.
        Miscellaneous information
        The provides functions to return miscellaneous information.
        Database server version information
        The provides functions to return information about the version of the database server.
      - The ESQL/C function library
        The function library provides functions for data conversion of data types.
    - Function descriptions
      This section gives comprehensive reference information about the functions that are valid within modules. It lists the function descriptions in alphabetical order, with syntax, usage information, and return values for the functions.
  - Developers Kit
    The Developers Kit (DBDK) guides contain information about the tools you can use to develop and package modules, which extend the functionality of HCL Informix® databases.
  - J/Foundation Developer's Guide
    The HCL® J/Foundation Developer's Guide describes how to write user-defined routines (UDRs) in the Java™ programming language for Informix®.
  - R-Tree Index User's Guide
    The HCL® Informix® R-Tree Index User's Guide describes the HCL Informix R-tree secondary access method and how to access and use its components.
  - User-Defined Routines and Data Types Developer's Guide
    The HCL® Informix® User-Defined Routines and Data Types Developer's Guide describes how to define new data types and enable user-defined routines (UDRs) to extend HCL Informix.
  - Virtual-Table Interface Guide
    The IBM® Informix® Virtual-Table Interface Programmer's Guide explains how to create a primary access method with the Virtual-Table Interface (VTI) so that users have a single SQL interface to HCL Informix tables and to data that does not conform to the storage scheme of HCL Informix.
  - Virtual-Index Interface Guide
    The IBM® Informix® Virtual-Index Interface Programmer's Guide explains how to create a secondary access method with the Virtual-Index Interface (VII) to extend the built-in indexing schemes of HCL Informix typically with a module.
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.

Selectivity and cost functions

The provides routines for accessing the MI_FUNCARG data type, which is the data type of all parameters of selectivity and cost functions.

Table 1. functions for accessing the **MI_FUNCARG** data type
Function category	function
Accessing the MI_FUNCARG data type	mi_funcarg_get_argtype() mi_funcarg_get_colno() mi_funcarg_get_constant() mi_funcarg_get_datalen() mi_funcarg_get_datatype()	mi_funcarg_get_distrib() mi_funcarg_get_routine_id() mi_funcarg_get_routine_name() mi_funcarg_get_tabid() mi_funcarg_isnull()