Thank you V. Shane Curtis, Kevininstructor and Acamar for reply,
Mr. V. Shane Curtis can you give me the coding standard details to follow and sample code,
in this please show me using exception handling display the error related error message
eg: for duplicate insertion exception display the error message "Duplicate insertion not allowed "
if data inserted "Data Saved Successfully"
and how can we throw the exception from one layer to another layer and display the proper error message in presentation layer