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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.
Designing and Implementing a Database
The Informix® Database Design and Implementation Guide provides information to help you design, implement, and manage your Informix databases. It includes data models that illustrate different approaches to database design and shows you how to use structured query language (SQL) to implement and manage your databases.
Basics of database design and implementation
Select data types
Data types
Character data types (GLS)
Large character objects: TEXT

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.
- Designing and Implementing a Database
  The Informix® Database Design and Implementation Guide provides information to help you design, implement, and manage your Informix databases. It includes data models that illustrate different approaches to database design and shows you how to use structured query language (SQL) to implement and manage your databases.

Large character objects: TEXT

The TEXT data type stores a block of text. It is designed to store self-contained documents: business forms, program source or data files, or memos. Although you can store any data in a TEXT item, Informix® tools expect a TEXT item to be printable, so restrict this data type to printable ASCII text.

TEXT values are not stored with the rows of which they are a part. They are allocated in whole disk pages, usually in areas separate from rows. For more information, see your Informix® Administrator's Guide.

The advantage of the TEXT data type over CHAR(n) and VARCHAR(m,r) is that the size of a TEXT data item has no limit except the capacity of disk storage to hold it. The disadvantages of the TEXT data type are as follows:

It is allocated in whole disk pages, so a short item wastes space.
Restrictions apply on how you can use a TEXT column in an SQL statement. (For more information about this restriction, see Use TEXT and BYTE data types.)