The following table summarizes the structure of the complex data
types.
Table 1. Collection types are complex
data types that are made up of elements, each of which is of the same
data type.
Collection types
Description
LIST
A group of ordered elements, each of which need
not be unique within the group.
MULTISET
A group of elements, each of which need not be
unique. The order of the elements is ignored.
SET
A group of elements, each of which is unique. The
order of the elements is ignored.
Table 2. ROW types are complex data types
that are made up of fields.
ROW types
Description
Named ROW type
Row types that are identified by their name.
Unnamed ROW type
Row types that are identified by their structure.
Complex data types can be nested. For example, you can construct
a ROW type whose fields include one or more sets, multisets, ROW types,
and lists. Likewise, a collection type can have elements whose data
type is a ROW type or a collection type.
Complex types that include opaque types inherit the following support
functions.
input
output
send
recv
import
export
import_binary
export_binary
assign
destroy
LO_handles
hash
lessthan
equal
lessthan (for ROW types only)
The topics that follow summarize the complex data types. For more
information, see the Informix Database Design and
Implementation Guide.