Overview of Datatypes

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

The datatypes recognized by Oracle are:

ANSI-supported datatypes

{ 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
}

Oracle built-in datatypes

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

Oracle-supplied datatypes

{ any_types
| XML_types
| spatial_types
| media_types
| expression_filter_type
}

User-defined datatypes

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