Row-type binary representation
The database server supports the following row types.
- Named row type
- A named row type is identified by its name. With the CREATE ROW
TYPE statement, you create a template of a row type. You can then
use this template to take the following actions:
- Use type inheritance
- Define columns that all have the same row type
- Assign a named row type to a table with the OF TYPE clause of the CREATE TABLE statement
- Unnamed row type
- An unnamed row type is identified by its structure. With the ROW keyword, you create a row type. This row type contains fields but has no user-defined name. Therefore, if you want a second column to have the same row type, you must specify all fields.
All row types use the same internal format to
store their values. For more information, see the HCL
Informix® Guide to SQL: Reference.
Tip: The internal format of a row type is often referred to
as its binary representation.
The DataBlade
API supports
the SQL row types with the following data type structures:
- A row descriptor (MI_ROW_DESC) provides information about the row type.
- A row structure (MI_ROW) holds the binary representation of the field values in the row type.
Important: The fields of a row type are comparable
to the columns in the row of a table. This similarity means that you
use the same DataBlade
API data
type structures to access row types that you do to access columns
in a row.