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Declaring Exceptions
The Exceptions can be declared only in the declarative part of the PL/SQL subprogram, block, or package. By introducing its name, you can declare an exception followed by the keyword EXCEPTION. In the illustration below, you declare an exception named past_due:
DECLARE
past_due EXCEPTION;
The Exception and variable declarations are alike. But keep in mind that, an exception is an error condition, not a data item. Unlike variables, the exceptions cannot appear in the assignment statements or the SQL statements. Though, the same scope rules apply to the variables and exceptions.
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Find the account numbers of all customers whose balance is more than 10,000 $
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