SQLPlus Define
A value can be assigned to a variable using the command DEF [INE] of SQL * PLUS.
Value defined to be used in a SELECT construction or a file of commands, the variable name prefixind with &. Variables can be emptied using UNDEF [INE].
DEFINE Command Syntax:
DEF[INE] [variable]|[variable = text]
DEFINE Command Examples:
DEFINE status = ‘EXPIRED’
DEFINE product_id
DEFINE product_id = 1521