ORA-01403: no data found

Pretty common oracle error. Raised when you are trying to fetch data from sql into a pl/sl variable and the sql does not return any data.

>> Using the data from this schema

What to do next

1. Re-Raise it with a error message that provides more context.

2. Suppress the error if this is a valid business scenario and do the necessary processing.
Example CASE : If a user has a preference to display the numbers in local currency, convert the amount, else, display in USD.

3. Functions, by design, do not raise the NO_DATA_FOUND exception, instead they return null to the calling program.