Overview of Data Types

A data type is a classification of a particular type of information or data. Each value manipulated by Oracle has a data type. The data type of a value associates a fixed set of properties with the value. These properties cause Oracle to treat values of one data type differently from values of another.

The data types recognized by Oracle are:

SQLQR955ANSI-supported data types

{ CHARACTER [VARYING] (size)
| { CHAR | NCHAR } VARYING (size)
| VARCHAR (size)
| NATIONAL { CHARACTER | CHAR }
     [VARYING] (size)
| { NUMERIC | DECIMAL | DEC }
     [ (precision [, scale ]) ]
| { INTEGER | INT | SMALLINT }
| FLOAT [ (size) ]
| DOUBLE PRECISION
| REAL
}

SQLQR956Oracle built-in data types

{ character_datatypes
| number_datatypes
| long_and_raw_datatypes
| datetime_datatypes
| large_object_datatypes
| rowid_datatypes
}

SQLQR957Oracle-supplied data types

{ any_types
| XML_types
| spatial_types
| media_types
| expression_filter_type
}

SQLQR958User-defined data types

User-defined data types use Oracle built-in data types and other user-defined data types to model the structure and behavior of data in applications.