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SQL programming
You can use the HCL Informix® implementation of the SQL language to develop applications for Informix database servers.
Guide to SQL: Reference
The Informix® Guide to SQL: Reference contains the reference information for the system catalog tables, data types, and environment variables of the HCL Informix dialect of the SQL language, as implemented in HCL Informix. These topics also include information about the stores_demo, sales_demo, and superstore_demo databases that are included with HCL Informix.
Data types
Every column in a table in a database is assigned a data type. The data type precisely defines the kinds of values that you can store in that column.
Built-In Data Types

SQL programming
You can use the HCL Informix® implementation of the SQL language to develop applications for Informix database servers.
- Guide to SQL: Syntax
- Guide to SQL: Reference
  The Informix® Guide to SQL: Reference contains the reference information for the system catalog tables, data types, and environment variables of the HCL Informix dialect of the SQL language, as implemented in HCL Informix. These topics also include information about the stores_demo, sales_demo, and superstore_demo databases that are included with HCL Informix.
  - System catalog tables
    The system catalog consists of tables and views that describe the structure of the database. Sometimes called the data dictionary, these table objects contain everything that the database knows about itself. Each system catalog table contains information about specific elements in the database. Each database has its own system catalog.
  - Data types
    Every column in a table in a database is assigned a data type. The data type precisely defines the kinds of values that you can store in that column.
    - Summary of data types
      HCL Informix® supports the most common set of built-in data types. Additionally, an extended set of data types are supported on the database server.
    - ANSI to Informix data type mapping
    - Description of Data Types
    - Built-In Data Types
      - Character Data Types
        The character data types store string values.
      - Large-Object Data Types
      - Time Data Types
    - Extended Data Types
    - Data Type Casting and Conversion
    - Operator Precedence
  - Environment variables
    Various environment variables affect the functionality of your HCL Informix® products. You can set environment variables that identify your terminal, specify the location of your software and define other parameters.
  - Appendixes
- Guide to SQL: Tutorial
  The Informix® Guide to SQL: Tutorial shows how to use basic and advanced structured query language (SQL) to access and manipulate the data in your databases. It discusses the data manipulation language (DML) statements as well as triggers and stored procedure language (SPL) routines, which DML statements often use.

Built-In Data Types

HCL Informix® supports the following built-in data types.


Category	Data Types
Character	CHAR, CHARACTER VARYING, LVARCHAR, NCHAR, NVARCHAR, VARCHAR, IDSSECURITYLABEL
Large-object	Simple-large-object types: BYTE, TEXT Smart-large-object types: BLOB, CLOB
Logical	BOOLEAN
Multirepresentational	BSON and JSON built-in opaque data types
Numeric	BIGINT, BIGSERIAL, DECIMAL, FLOAT, INT8, INTEGER, MONEY, SERIAL, SERIAL8, SMALLFLOAT, SMALLINT
Time	DATE, DATETIME, INTERVAL