Oracle Data Types
In Oracle, the main data types are:
NUMBER – the number is a numeric data type and is used to define numeric columns or variables.
VARCHAR2 – the varchar2 is a variable-length character and is used to define variable-length character columns or variables.
DATE – the date is the date and time data type and is used to define date columns or variables.
PLS_INTEGER – the pls_integer datatype is used to store signed integers. PLS_INTEGER values require less storage than NUMBER values and is faster than NUMBER.
CHAR – the char datatype is used to store fixed-length character data.
TIMESTAMP – the datatype TIMESTAMP extends the datatype DATE, stores the year, month, day, hour, minute, and second.
TIMESTAMP WITH TIME ZONE – extends the TIMESTAMP, includes a time-zone displacement.
BLOB – the BLOB datatype is used to store large binary objects in the database.
CLOB – the CLOB datatype is used to store large blocks of character data in the database.
NCHAR – the NCHAR datatype is used to store fixed-length national character data.
NVARCHAR2 – the NVARCHAR2 datatype to store variable-length Unicode character data.