Oracle SQL*Plus: The Definitive Guide

VARIABLE

The VARIABLE command is used to declare bind variables. Bind variables are discussed in Chapter 7. They are real variables that can be used within a PL/SQL block or SQL statement.

VAR[IABLE] var_name
             
            data_type

where:

VAR[IABLE]

Is the command, which may be abbreviated to VAR.

var_name

Is whatever name you want to give the variable. A variable name must start with a letter, but after that, the name may contain any combination of letters, digits, underscores, pound signs, and dollar signs. 30 characters is the maximum length for a variable name.

data_type

Is the datatype of the variable. The following datatypes are allowed:

NUMBER

This results in a floating-point number, and is the same as a NUMBER variable in PL/SQL or a NUMBER column in a table. Unlike PL/SQL, SQL*Plus does not let you specify a length or a precision, so a declaration like NUMBER (9,2) would not be allowed.

CHAR [(length)]

Results in a fixed-length character string. Length is optional. If it’s omitted, you get a one-character string.

NCHAR [(length)]

Results in a fixed-length character string in the national character set. Length is optional. If it’s omitted, you get a one-character string.

VARCHAR2 (length)

Results in a variable-length character string.

NVARCHAR2 (length)

Results in a variable-length character string using the national language character set.

CLOB

Results in a character large object variable.

NCLOB

Results in a character large object variable using the national language character set.

REFCURSOR