What is a data type?

• Data type determines the size and the range of values that can be stored within the variable or column.
• Data types also decides the set of operations that can be applied to the variable.

Every Oracle table column is associated with a data type. Data type is also required to declare a variable or a constant.

Oracle supplies the following built-in datatypes:

• character datatypes
  • CHAR
  • NCHAR
  • VARCHAR2 and VARCHAR
  • NVARCHAR2
  • CLOB
  • NCLOB
  • LONG
• NUMBER datatype
• DATE datatype
• binary datatypes
  • BLOB
  • BFILE
  • RAW
  • LONG RAW