ALLBASE/SQL Reference Manual (36216-90216)

Chapter 7 207
Data Types
7 Data Types
Every value in SQL belongs to some data type. A data type is associated with each value
retrieved from a table, each constant, and each value computed in an expression.
This chapter discusses data types. The following sections are presented:
• Type Specifications
• Value Comparisons
• Overflow and Truncation
• Underflow
• Type Conversion
• Null Values
• Decimal Operations
• Date/Time Operations
• Binary Operations
• Long Operations
• Native Language Data
A data type defines a set of values. Reference to a previously defined data type is a
convenient way of specifying the set of values that can occur in some context. For example,
in SQL the type INTEGER is defined as the set of integers from −2,147,483,648 through
+2,147,483,647, plus the special value NULL. If you define a column with type INTEGER,
each value stored in the column must be either an integer in the range −2,147,483,648
through +2,147,483,647, or a null value (if NOT NULL is not specified).